Read the passage carefully and choose the best answer to each question out of the four alternatives.

Insects are found throughout the world except on the poles. Fossil records indicate that many species exist today in much the same form as they did 200 million years ago. Their enormous biological success is attributed to their small size, the remarkable adaptive abilities of the group as a whole and the enormous variety in body structure and way of life. The mouth parts may be adapted to chewing, sucking or lapping and the legs for running, jumping or swimming. Insects may feed on plants or prey upon other small animals or parasitize larger ones. They may be omnivorous or highly specialized in their diets. They display a remarkable variety of adaptive shapes and colours that may serve as camouflage. Some have stinging spines or hair and blistering or noxious secretions used for defence.