Can you help me with biology?

[schoolsux!]

Which of the following statements is false?
A) Insects lose very little water by using a tracheal system.
B) The main problem facing any air-breathing animal is the loss of water to the air by evaporation.
C) The tracheal system of insects consists of a series of branching air tubes that extend from the surface to deep inside the body.
D) A terrestrial animal spends much more energy than an aquatic animal ventilating its respiratory surface.
E) The circulatory system of insects is not involved in transporting oxygen.

Compared to the vital capacity, how much air can lungs actually hold?
A) always less
B) sometimes less
C) always more
D) sometimes more
E) always the same amount

The function of air sacs in birds is to
A) lighten the bird.
B) adjust the temperature of air.
C) clean the air.
D) permit one-way ventilation of the lungs.
E) store air for times of physical exertion.