✅ Answer: (C) Walking
Explanation: Life processes are essential functions that maintain life — Nutrition, Respiration, Transportation, Excretion, Reproduction, Control & Coordination, and Growth. Walking is a physical activity, not a fundamental life process. This is a definitional question common in GNMEE.

✅ Answer: (B) Photosynthesis
Explanation: Photosynthesis = CO₂ + H₂O + sunlight → Glucose + O₂. It occurs in the chloroplasts using the green pigment chlorophyll. Respiration releases energy; transpiration involves water loss through leaves.

✅ Answer: (C) Mitochondria
Explanation: Mitochondria produce ATP (energy) through cellular respiration. They are called the powerhouse of the cell. Chloroplasts are the site of photosynthesis in plant cells.

✅ Answer: (C) Oxygen
Explanation: Aerobic respiration: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + Energy (ATP). Anaerobic respiration occurs without oxygen and produces lactic acid (in animals) or ethanol (in yeast).

✅ Answer: (B) Pulmonary vein
Explanation: The pulmonary vein is the only vein that carries oxygenated blood — from lungs to the left atrium of the heart. The pulmonary artery carries deoxygenated blood from the heart to the lungs. This is a classic GNMEE trap question.

✅ Answer: (C) Bowman's capsule
Explanation: The Bowman's capsule surrounds the glomerulus and is the site of ultrafiltration — blood is filtered under pressure here. The filtered liquid (glomerular filtrate) then passes through the nephron tubules.

✅ Answer: (C) Mouth
Explanation: Salivary amylase (ptyalin) in the mouth begins starch digestion by breaking it into maltose. Protein digestion begins in the stomach. Fat digestion occurs in the small intestine.

✅ Answer: (B) Water absorption
Explanation: The large intestine (colon) absorbs water and mineral salts from undigested food material. Most nutrient absorption occurs in the small intestine. The large intestine also houses gut bacteria.

✅ Answer: (C) Stomata
Explanation: Transpiration — the evaporation of water from plant surfaces — primarily occurs through stomata (tiny pores on leaf surfaces). The opening and closing of stomata is regulated by guard cells.

✅ Answer: (C) Red blood cells
Explanation: Haemoglobin (Hb) is the iron-containing protein in Red Blood Cells (RBCs/erythrocytes) that binds oxygen for transport throughout the body. Low Hb = anaemia — directly relevant to nursing practice.

✅ Answer: (C) Pepsin
Explanation: Pepsin is secreted by the stomach and works in the acidic environment (HCl) to break proteins into peptides. Trypsin acts in the small intestine. Amylase breaks starch; lipase breaks fats.

✅ Answer: (A) Nephron
Explanation: Each kidney contains approximately 1 million nephrons — the structural and functional units responsible for filtering blood and forming urine. Neurons are nerve cells; alveoli are in the lungs; villi are in the small intestine.

✅ Answer: (C) Oxygen
Explanation: Photosynthesis splits water molecules (photolysis) and releases oxygen as a by-product: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂. The oxygen comes from water, not from CO₂.

✅ Answer: (B) Urea
Explanation: Humans are ureotelic — they excrete urea as the main nitrogenous waste product. Urea is produced in the liver from amino acid breakdown and excreted via kidneys. Uric acid is the main excretory product in birds and reptiles.

✅ Answer: (D) Interstitial fluid
Explanation: Interstitial (tissue) fluid is plasma that leaks out of capillaries into the spaces between cells, delivering nutrients and oxygen directly to cells. When it enters lymph capillaries it becomes lymph.

✅ Answer: (B) Asexual reproduction
Explanation: Asexual reproduction does not involve gametes. It produces genetically identical offspring (clones) from a single parent. Examples: budding in Hydra, binary fission in Amoeba, spore formation in Rhizopus.

✅ Answer: (B) Binary fission
Explanation: Amoeba reproduces by binary fission — the parent cell divides into two equal daughter cells. Budding occurs in Hydra and yeast. Spore formation occurs in Rhizopus (bread mould). Fragmentation occurs in Spirogyra (algae).

✅ Answer: (C) Fallopian tube
Explanation: The sperm and egg (ovum) meet and fuse (fertilisation) in the Fallopian tube (oviduct). The resulting zygote then travels to the uterus and implants in the uterine wall for development.

✅ Answer: (C) Testes
Explanation: Testes (singular: testis) produce sperm (spermatogenesis) and also secrete testosterone. The epididymis stores and matures sperm; the vas deferens carries sperm out; seminal vesicles provide fluid for semen.

✅ Answer: (B) Progesterone
Explanation: Progesterone is produced by the corpus luteum (after ovulation) and maintains the uterine lining (endometrium) for implantation and sustains pregnancy. Fall in progesterone triggers menstruation. Directly relevant nursing knowledge.

✅ Answer: (C) Oxygen, nutrients, and removes waste
Explanation: The placenta is the interface between mother and foetus. It provides oxygen and nutrients from maternal blood to foetal blood, and removes CO₂ and metabolic waste from foetal blood to maternal blood. Essential nursing knowledge.

✅ Answer: (B) Angiosperms
Explanation: Double fertilisation is unique to flowering plants (angiosperms): one sperm fertilises the egg (forming zygote), while another sperm fuses with the polar nuclei (forming endosperm). Gymnosperms have single fertilisation.

✅ Answer: (B) Hydra
Explanation: Hydra reproduces asexually by budding — a small bud grows on the parent body, develops into a new individual, and then detaches. Yeast also reproduces by budding. Amoeba = binary fission; Rhizopus = spore formation; Plasmodium = multiple fission.

✅ Answer: (B) Self-pollination
Explanation: Self-pollination = pollen from the anther of a flower transferred to the stigma of the same flower or another flower on the same plant. Cross-pollination = pollen transferred between flowers on different plants.

✅ Answer: (C) 9 months
Explanation: The normal human gestation period is approximately 9 months (38–40 weeks from fertilisation to birth). A baby born before 37 weeks is considered premature. This is fundamental nursing knowledge.

✅ Answer: (B) Potato through tubers
Explanation: Vegetative propagation is asexual reproduction in plants using vegetative parts (roots, stems, leaves). Potato reproduces through underground stem tubers (the "eyes"). Other examples: ginger through rhizomes, onion through bulbs, Bryophyllum through leaves.

✅ Answer: (C) Helper T-cells (CD4+)
Explanation: HIV (Human Immunodeficiency Virus) targets and destroys CD4+ T helper cells — the key cells of the immune system. Progressive destruction of these cells leads to AIDS (Acquired Immunodeficiency Syndrome). Critical nursing knowledge for infection control.

✅ Answer: (B) Gregor Mendel
Explanation: Gregor Johann Mendel (1822–1884) is the Father of Genetics. He conducted experiments on pea plants (Pisum sativum) and formulated the laws of inheritance. Charles Darwin proposed the Theory of Evolution by Natural Selection.

✅ Answer: (B) 3:1
Explanation: F1 = all Tt (tall). F2 from Tt × Tt = 1 TT : 2 Tt : 1 tt → phenotypic ratio = 3 tall : 1 dwarf. Tall is dominant over dwarf. This is Mendel's Law of Segregation. The 9:3:3:1 ratio applies to a dihybrid cross.

✅ Answer: (C) Heterozygous
Explanation: Tt = two different alleles (one dominant T, one recessive t) = heterozygous. TT = homozygous dominant. tt = homozygous recessive. Heterozygous organisms show the dominant phenotype but carry the recessive allele.

✅ Answer: (C) The combination of sex chromosomes
Explanation: Females are XX; males are XY. The sex of the offspring is determined by whether the sperm carries an X or Y chromosome. The egg always contributes an X chromosome.

✅ Answer: (C) Genetic (inherited) disease
Explanation: Sickle cell anaemia is caused by a mutation in the haemoglobin gene — it is a genetic/inherited disease passed from parents to offspring. It is not infectious (not spread person-to-person) and not a chromosomal disorder like Down syndrome.

✅ Answer: (B) Heritable characteristics of populations over generations
Explanation: Evolution refers to changes in the heritable (genetic) traits of a population over successive generations, driven by natural selection, mutation, migration, and genetic drift. It happens at the population level, not to individuals.

✅ Answer: (C) Charles Darwin
Explanation: Charles Darwin proposed the Theory of Evolution by Natural Selection in 1859 in his book "On the Origin of Species." The core idea: organisms with favourable traits survive and reproduce more — "survival of the fittest."

✅ Answer: (B) Mutation
Explanation: A mutation is a sudden, permanent change in the DNA sequence of a gene. Mutations can be spontaneous or induced (by radiation, chemicals). They are the ultimate source of genetic variation on which natural selection acts.

✅ Answer: (B) Sex-linked recessive disease
Explanation: Haemophilia is caused by a recessive gene on the X chromosome. Since males have only one X (XY), a single copy of the mutated gene causes the disease. Females (XX) need two copies to be affected — making them rare carriers. A key nursing knowledge concept.

✅ Answer: (C) Remnants of organs that were functional in ancestors
Explanation: Vestigial organs are reduced, non-functional remnants of structures that were useful in evolutionary ancestors. Examples in humans: appendix, coccyx (tailbone), wisdom teeth, ear-wiggling muscles. They provide evidence for evolution.

✅ Answer: (C) Dominant
Explanation: In a cross between two pure-breeding parents (e.g., TT × tt), the F1 generation shows only the trait of one parent — this trait is called dominant. The other trait (recessive) reappears in the F2 generation.

✅ Answer: (B) Neuron
Explanation: A neuron (nerve cell) is the basic structural and functional unit of the nervous system. It consists of a cell body (soma), dendrites (receive signals), and an axon (transmits signals). The nephron is the functional unit of the kidney.

✅ Answer: (B) Spinal cord
Explanation: Reflex actions are automatic, rapid responses to stimuli controlled by the spinal cord — without brain involvement. The reflex arc path: Receptor → Sensory nerve → Spinal cord → Motor nerve → Effector. E.g., knee-jerk reflex, withdrawing hand from fire.

✅ Answer: (C) Pituitary
Explanation: The pituitary gland (located at the base of the brain) is called the master gland because it secretes hormones that regulate other endocrine glands (thyroid, adrenal, gonads). It is controlled by the hypothalamus.

✅ Answer: (C) Beta cells of Islets of Langerhans
Explanation: Insulin is produced by beta (β) cells of the Islets of Langerhans in the pancreas. It lowers blood glucose levels. Alpha cells secrete glucagon (raises blood glucose). Deficiency of insulin → Diabetes mellitus. Critical nursing knowledge.

✅ Answer: (C) Adrenal gland
Explanation: Adrenaline (epinephrine) is secreted by the adrenal medulla (inner part of the adrenal gland). It is the "fight or flight" hormone — increases heart rate, dilates pupils, raises blood glucose in emergency situations.

✅ Answer: (B) Metabolic rate
Explanation: Thyroxine (T4), secreted by the thyroid gland, regulates the body's basal metabolic rate (BMR). It requires iodine for production. Deficiency = hypothyroidism (goitre); excess = hyperthyroidism. Iodised salt prevents goitre.

✅ Answer: (B) Light
Explanation: Phototropism = growth/movement in response to light. Shoots are positively phototropic (grow towards light); roots are negatively phototropic (grow away from light). This is controlled by the plant hormone auxin (IAA).

✅ Answer: (C) Cerebellum
Explanation: The cerebellum (hindbrain) is responsible for motor coordination, balance, and fine movement. Cerebrum = thinking, memory, speech. Medulla oblongata = involuntary functions (heart rate, breathing). Hypothalamus = temperature regulation, hunger, thirst.

✅ Answer: (B) Neurotransmitter
Explanation: When a nerve impulse reaches the end of a neuron (pre-synaptic terminal), it triggers the release of neurotransmitters (e.g., acetylcholine, dopamine) into the synapse. These bind to receptors on the next neuron, passing the signal. Key pharmacology foundation.

✅ Answer: (C) Gravity
Explanation: Geotropism (gravitropism) = response to gravity. Roots are positively geotropic (grow downward). Shoots are negatively geotropic (grow upward). Hydrotropism = response to water; Thermotropism = response to temperature.

✅ Answer: (C) Decomposition
Explanation: Decomposition = breakdown of dead organic matter (leaves, dead animals) by decomposers (bacteria, fungi) into simpler inorganic substances (CO₂, water, minerals). This recycles nutrients back into the ecosystem.

✅ Answer: (C) Kitchen vegetable scraps
Explanation: Biodegradable waste = material that can be broken down by microorganisms in nature. Examples: food scraps, paper, cotton, leaves. Non-biodegradable: plastic, glass, metal, DDT — these persist in the environment for decades.

✅ Answer: (B) Biomagnification
Explanation: Biomagnification = progressive increase in the concentration of non-biodegradable substances (e.g., DDT, mercury) as they move up the food chain. Organisms at the top of the food chain accumulate the highest concentrations.

✅ Answer: (A) 10%
Explanation: According to Lindeman's 10% law, only 10% of energy at one trophic level is transferred to the next. The remaining 90% is lost as heat (respiration, movement). This is why food chains are rarely longer than 4–5 levels.

✅ Answer: (B) Ultraviolet rays
Explanation: The stratospheric ozone layer absorbs harmful ultraviolet (UV) radiation from the sun. Depletion of the ozone layer (by CFCs — chlorofluorocarbons) leads to increased UV reaching Earth, causing skin cancer and cataracts.

✅ Answer: (C) Forests
Explanation: The Chipko Movement (1973, Uttarakhand) involved villagers, especially women, hugging (chipko = to hug/cling) trees to prevent commercial logging. It is a landmark environmental conservation movement in India.

✅ Answer: (D) Solar energy
Explanation: Renewable energy sources are naturally replenished on a human timescale: solar, wind, hydro, geothermal, biomass. Coal, petroleum, and natural gas are fossil fuels — non-renewable and take millions of years to form.

✅ Answer: (B) Xylem
Explanation: Xylem conducts water and dissolved minerals from roots to leaves (upward movement). Phloem conducts prepared food (sugars) from leaves to other parts of the plant (both directions). Together they form the vascular bundle.

✅ Answer: (C) Heart wall
Explanation: Cardiac muscle (myocardium) is found only in the heart wall. It is involuntary, striated, and has intercalated discs for coordinated contraction. Biceps = skeletal (voluntary) muscle; Stomach = smooth (involuntary) muscle; Diaphragm = skeletal muscle.

✅ Answer: (C) Cover surfaces and line cavities
Explanation: Epithelial tissue covers body surfaces (skin), lines cavities (intestine, lungs, blood vessels), and glands. It acts as a protective barrier, selective permeable layer, and secretory surface.

✅ Answer: (B) Tendon
Explanation: Tendon = connects muscle to bone (tough, fibrous). Ligament = connects bone to bone at joints (slightly elastic). Cartilage = flexible connective tissue at joints and in ears, nose. Nurses commonly encounter these in musculoskeletal injuries.

✅ Answer: (B) Mitosis
Explanation: Mitosis produces two genetically identical daughter cells from one parent cell — used for growth, repair, and replacement of body cells. Meiosis produces four genetically diverse haploid cells — used for sexual reproduction (gamete formation).

✅ Answer: (C) 2H₂ + O₂ → 2H₂O
Explanation: A combination reaction = two or more substances combine to form one new product. (A) = decomposition; (B) = thermal decomposition; (D) = displacement reaction. Only (C) involves two reactants combining into one product.

✅ Answer: (C) Oxidation reaction
Explanation: Rusting = iron + oxygen + water → iron oxide (rust). Iron loses electrons (is oxidised) and combines with oxygen. The full process: 4Fe + 3O₂ + xH₂O → 2Fe₂O₃.xH₂O (rust = hydrated iron oxide).

✅ Answer: (B) Law of conservation of mass
Explanation: A balanced chemical equation has the same number of atoms of each element on both sides — obeying the Law of Conservation of Mass (Lavoisier): "Matter is neither created nor destroyed in a chemical reaction."

✅ Answer: (A) Less reactive metal
Explanation: In a displacement reaction, a more reactive metal displaces a less reactive metal from its salt solution. Example: Zn + CuSO₄ → ZnSO₄ + Cu (Zinc is more reactive than copper, so it displaces copper).

✅ Answer: (B) Release heat to surroundings
Explanation: Exothermic reactions release energy (usually heat) to the surroundings — the products have less energy than the reactants. Examples: combustion, neutralisation, respiration. Endothermic reactions absorb heat: photosynthesis, electrolysis.

✅ Answer: (B) Mg(OH)₂
Explanation: Milk of magnesia = magnesium hydroxide Mg(OH)₂ — a white suspension used as an antacid to neutralise excess stomach acid. Directly relevant nursing pharmacology knowledge. MgSO₄ (Epsom salt) is used as a laxative.

✅ Answer: (C) Neutralisation
Explanation: Neutralisation: Acid + Base → Salt + Water. Example: HCl + NaOH → NaCl + H₂O. The products are neutral (pH ~7). This principle underlies antacid use in medicine — a core nursing knowledge concept.

✅ Answer: (C) Red
Explanation: Blue litmus turns red in acidic solutions (pH < 7). Red litmus turns blue in basic/alkaline solutions (pH > 7). In neutral solutions (pH = 7), there is no colour change. Classic Class 10 chemistry indicator question.

✅ Answer: (B) 7
Explanation: Pure water is neutral with a pH of 7. pH scale: 0–6.9 = acidic; 7 = neutral; 7.1–14 = basic/alkaline. The human blood pH is 7.35–7.45 (slightly alkaline) — deviation causes acidosis or alkalosis, both medical emergencies.

✅ Answer: (C) Acetic acid
Explanation: Vinegar = dilute acetic acid (ethanoic acid, CH₃COOH). Citric acid is in lemon juice. HCl is in gastric juice (stomach acid). H₂SO₄ is in car batteries. These everyday acid associations are commonly tested in GNMEE.

✅ Answer: (B) NaCl
Explanation: Sodium chloride (NaCl) = common salt. NaOH = sodium hydroxide (caustic soda). Na₂CO₃ = washing soda. NaHCO₃ = baking soda (sodium bicarbonate — used as antacid). These are the "sodium family" of compounds commonly tested.

✅ Answer: (C) Hydrogen
Explanation: Zn + 2HCl → ZnCl₂ + H₂↑. Hydrogen gas is produced, which burns with a "pop" sound when a burning splint is brought near. This "pop test" identifies hydrogen gas — a standard Class 10 lab experiment.

✅ Answer: (B) Carbon dioxide
Explanation: 2NaHCO₃ → Na₂CO₃ + H₂O + CO₂. The CO₂ gas released makes bread and cakes rise during baking (acts as a leavening agent). NaHCO₃ is also used as an antacid to neutralise excess stomach acid.

✅ Answer: (C) Sulphuric acid
Explanation: Strong acids fully dissociate in water: HCl, H₂SO₄, HNO₃. Weak acids partially dissociate: CH₃COOH (acetic), H₂CO₃ (carbonic), citric acid. Sulphuric acid (H₂SO₄) is the "king of chemicals" — a strong, corrosive acid.

✅ Answer: (C) Mg(OH)₂
Explanation: Antacids are mild bases that neutralise excess HCl in the stomach. Mg(OH)₂ (milk of magnesia) and Al(OH)₃ are common antacids. NaOH is too strong and corrosive to use internally. HCl and H₂SO₄ are acids — they would worsen acidity.

✅ Answer: (C) Silver
Explanation: Silver is the best conductor of electricity, followed by copper, then gold. However, copper is used in electrical wiring because it is cheaper and nearly as conductive as silver. Iron is a poor conductor by comparison.

✅ Answer: (C) Sodium
Explanation: Sodium is an extremely reactive metal — it reacts vigorously with air (forms Na₂O) and water (forms NaOH + H₂ gas — potentially explosive). It is therefore stored under kerosene oil to prevent contact with moisture and oxygen.

✅ Answer: (B) Ductility
Explanation: Ductility = property of a metal that allows it to be drawn into thin wires. Gold is the most ductile metal. Malleability = ability to be beaten into thin sheets (e.g., gold leaf). Aluminium is both malleable and ductile.

✅ Answer: (C) Graphite (Carbon)
Explanation: Graphite (an allotrope of carbon) is the only non-metal that conducts electricity because its layered structure allows free movement of electrons along the layers. It is used in electrodes and pencil leads. All other non-metals are poor conductors.

✅ Answer: (C) Methane
Explanation: Methane (CH₄) is the simplest alkane (saturated hydrocarbon) with 1 carbon atom. It is the main component of natural gas. Homologous series: methane (C1) → ethane (C2) → propane (C3) → butane (C4).

✅ Answer: (B) An antiseptic and solvent
Explanation: Ethanol (C₂H₅OH) is used as: (1) An antiseptic (70% ethanol kills bacteria on skin — used in hand sanitisers), (2) A solvent in medicines and perfumes, (3) A fuel (biofuel). Its antiseptic use is directly relevant to nursing practice.

✅ Answer: (C) Diamond
Explanation: Diamond is an allotrope of carbon and the hardest natural substance known (Mohs scale = 10). Its hardness comes from a rigid 3D tetrahedral covalent lattice structure. Graphite (soft, layered), charcoal (amorphous), and fullerene are other carbon allotropes.

✅ Answer: (C) 10 V
Explanation: V = IR = 2 × 5 = 10 V. Ohm's Law: Voltage (V) = Current (I) × Resistance (R). This formula and simple numerical substitution is the most-tested Physics question type in GNMEE.

✅ Answer: (D) Ohm (Ω)
Explanation: SI units: Resistance = Ohm (Ω), Current = Ampere (A), Voltage = Volt (V), Power = Watt (W), Energy = Joule (J). Named after Georg Simon Ohm. 1 Ohm = resistance when 1 V produces a current of 1 A.

✅ Answer: (C) 2Ω
Explanation: Parallel resistors: 1/R = 1/R₁ + 1/R₂ = 1/4 + 1/4 = 2/4 = 1/2. So R = 2Ω. Key rule: parallel combination always gives resistance LESS than either individual resistor. Series gives resistance MORE than either.

✅ Answer: (B) P = VI
Explanation: Electric Power P = VI (also P = I²R = V²/R). Power is measured in Watts (W). 1 kilowatt (kW) = 1000 W. The commercial unit of energy is the kilowatt-hour (kWh) = "one unit" of electricity on your electricity bill.

✅ Answer: (C) Current
Explanation: In a series circuit, the same current flows through all components. Voltage is distributed (divides across components). In a parallel circuit, voltage remains the same across all components, while current divides.

✅ Answer: (B) Low melting point and high resistance
Explanation: A fuse wire must melt quickly (low melting point) when excess current flows, breaking the circuit. High resistance ensures it heats up quickly under excess current. Alloys of lead and tin with low melting points (~183°C) are used.

✅ Answer: (C) Electric iron
Explanation: The heating effect of current (Joule's law: H = I²Rt) is used in: electric iron, electric heater, toaster, incandescent bulb, fuse. Electric fan and motor use the magnetic effect. Transformer uses electromagnetic induction.

✅ Answer: (B) Increases
Explanation: For metallic conductors (like copper, iron), resistance increases with temperature because higher temperature causes more atomic vibrations, increasing collisions with electrons and impeding current flow. Note: For semiconductors and insulators, the opposite is true.

✅ Answer: (C) 3,600,000 J (3.6 × 10⁶ J)
Explanation: 1 kWh = 1 kW × 1 hour = 1000 W × 3600 s = 3,600,000 J = 3.6 MJ. This is the commercial unit of electrical energy. One "unit" on your electricity bill = 1 kWh.

✅ Answer: (A) Angle of incidence
Explanation: The First Law of Reflection: The angle of incidence (i) = angle of reflection (r). Both angles are measured from the normal to the reflecting surface. The incident ray, reflected ray, and normal are all in the same plane.

✅ Answer: (C) Convex mirror
Explanation: Convex mirrors are used as rear-view mirrors because they provide a wider field of view (diverge light) and always produce an upright, diminished virtual image — allowing the driver to see more of the road behind them.

✅ Answer: (B) Bent away from the normal
Explanation: Snell's Law: When light enters a rarer medium (e.g., glass → air), it speeds up and bends away from the normal (angle of refraction > angle of incidence). When entering a denser medium, it bends towards the normal.

✅ Answer: (B) Concave lens
Explanation: Myopia = nearby objects clear, distant objects blurred (image forms in front of the retina). Corrected by a concave (diverging) lens to move the image back onto the retina. Hyperopia = far-sighted = corrected by convex (converging) lens.

✅ Answer: (D) Both B and C
Explanation: Rayleigh scattering: shorter wavelengths (blue) scatter more than longer wavelengths (red). During the day → blue light scattered → sky appears blue. At sunrise/sunset → light travels longer path → blue scattered away → only red/orange reaches us → red sky.

✅ Answer: (C) Concave mirror
Explanation: Concave mirrors are used by dentists and ENT doctors because they produce a magnified, upright (virtual) image when the object is within the focal length. This makes small details (teeth, throat) easier to examine. Also used in torches/searchlights to focus light.

✅ Answer: (C) Generator
Explanation: Generator (dynamo) converts mechanical energy → electrical energy (using electromagnetic induction). Motor converts electrical energy → mechanical energy. Transformer changes AC voltage levels. Capacitor stores electrical charge.

✅ Answer: (C) Force on a current-carrying conductor in a magnetic field
Explanation: Fleming's Left-Hand Rule (for motors): thumb = direction of force/motion, index finger = direction of magnetic field (B), middle finger = direction of current (I). Fleming's Right-Hand Rule is used for generators (direction of induced current).

✅ Answer: (C) Strong magnetic fields and radio waves
Explanation: MRI (Magnetic Resonance Imaging) uses powerful magnetic fields (aligned hydrogen atoms in body) and radio waves to produce detailed internal body images. No ionising radiation (unlike X-rays). Nurses must be aware of MRI safety protocols — no metallic implants near MRI machines.