Animals use evaporative cooling via latent heat

Steps:

• Identify latent heat of vaporization as energy absorbed when water evaporates, cooling the surface without temperature change.
• Evaluate statements for accuracy in explaining animal cooling mechanisms like sweating or panting.
• Check which statements correctly link evaporation to heat loss in hot environments.
• Select option matching correct statements: 3 and 4.

Why C is correct:

• Latent heat of vaporization (L = 2260 kJ/kg for water) requires energy input for phase change, directly cooling animals as water evaporates from skin or lungs.

Why the others are wrong:

• A includes incorrect statements 1 and 2, which misrepresent evaporation physics.
• B pairs valid 4 with invalid 1, ignoring core heat transfer principle.
• D omits 4, missing key evaporation role in thermoregulation.

Not enough information on exact statements 1–4 to detail further.

Final answer: C