题目内容：

阅读下列短文，从每题所给的A、B、C和D项中，选出最佳选项并在答题卡上将该项涂黑。

Do you knowwhy different animals or pestshave their special colors? Colorsin themseem to be used mainly to protect themselves.

Some birds like eating locusts(蝗虫), but birds cannot easily catch them. Why? It is becauselocusts change their colorstogether with the change of the colorsof crops(庄稼). When cropsare green, locusts look green. But as the harvest(收获) time comes, locusts change to the samebrown coloras crops have. Some other pests with different colorsfrom plants are easily foundand eaten by others. So they have to hide themselves for lives and appear only at night.

If you study the animal life, you'll find the main use of coloringis to protect themselves. Bears,lions and other animals move quietly through forests. They cannot be easily seen by hunters(猎人). This isbecause they have the colorsmuch like the trees.

Have you ever found an even strangeract? A kind of fish in the sea can send out a kind ofvery black liquid(液体) when it faces danger. While the liquid spreads over(散开), its enemiescannot find it. And it immediately swims away. So it has lived up to now though it is not strong at all.

1.From the passage we learn that locusts __________.

A. are small animals

B. are easily found by birds

C. are dangerous to their enemies

D. change their colorsto protect themselves

2. How can pests with different colorsfrom plants keep out of danger?

A. They run away quickly.

B. They have the colorsmuch like their enemies.

C. They hide themselves by day and appear at night.

D. They have to move quietly.

3. Bears and lions can keep safe because __________.

A. they have the colorsmuch like the trees

B. they move quietly

C. they like brown and grey colors

D. they live in forests

4.Why can the kind of fish live up to now?

A. Because it is verystrong.

B. Because the liquid it sends out can help it escape from its enemies.

C. Because the liquid it sends out can kill its enemies.

D. Because it swims faster than any other fish.

5.Which is the best title for this passage?

A. The Change of Colorsfor Animals and Pests.

B. Colorsof Different Animals and pests.

C. The Main Use of Colorsfor Animals and Pests.

D. Some Animals and Pests.