In the dark night ofthe desert,a group of U.S.Air Force scientists is testing a new device for amissile to target.Designed to seek out the heat of an enemy aircraft engine,itis

now going throughits paces by tracing the movement of a flashlight waving thirty feet away inthe darkness.A hundred yards away,unseen by the man,a rattlesnake sliding

between the stonessenses a patch of warmth. Although the snake's mechanism is small enough to bepacked into a head the size of a nut,it can detect a change in temperature

of one-thousandth ofa degree.With a sound the snake closes in and strikes for the kill.

Whenever we look inthe animal world we find the same story.Almost anything that man can do,naturehas already done better. So,it is for the purpose of learning from nature

that a new sciencecalled bionics has grown up.Its aim is to find out how animal's instrumentswork so that man can copy them for his own purpose.

Imagine being ableto know a friend several miles off by his smell. Male silk moths can do this.Their antennae are so sensitive to the chemical odor of female moths that they

can detect theirpresence by picking up only one molecule of the chemical.Even with their mostsensitive instruments, human cannot approach this perfection.

Studying beetle'seyes has already paid off. A group of scientists in Germany found that a beetle canaccurately measure with its eyes the speed of moving background.After

finding out how abeetle accomplishes this scientists built a machine that operated on the sameprinciple.This instrument is able to determine the ground speed of moving

aircraft with a highdegree of accuracy.The goal forbionics is to______.

A.explain how animaldevices work

B.copy animalprocesses with man-made machines

C.prove theusefulness of this science

D.apply science tothe study of animals