题目内容：

    Many people say dolphins are very itelligent. They seem to be able to think, understand, and learn things quickly. But are they smart like humans or are they more like cats or dogs? Dolphins use their brains differently from people. But scientists say dolphin intelligence and human intelligence are similar in some ways. How?

Like humans, every dolphin has its own name. The name is a special whistle. Each dolphin chooses a specific whistle for itself, usually by its first birthday. Actually, scientists think dolphins, like people, “talk” to each other about a lot of things, such as their age, their feelings, or finding food. And, like humans, dolphins use a system of sounds and body language to communicate. But understanding their conversations is not easy for humans. No one speaks “dolphin” yet, but some scientists are trying to learn.

Dolphins are also social animals. They live in groups, and they often join others from different groups to play games and have fun—just like people. In fact, playing together is something only intelligent animals do.

Dolphins and humans are similar in another way: both species make plans to get something they want. In the seas of southern Brazil, for example, dolphins use an interesting strategy to get food. When fish are near a boat, dolphins show signs to the fishermen to put their nets in the water. Using this method, the men can catch a lot of fish. What is the advantage for the dolphins in doing so? They get to eat some of the fish that escape from the net.

根据材料内容选择最佳答案。

1.What does a dolphin often use as its name?

A.A body language. B.A special whistle.

C.Its feeling. D.Its age.

2.What does the underlined word "species" mean in Chinese?

A.方法 B.片段 C.物种 D.声音

3.Why do dolphins help the fishermen?

A.To catch a lot of fish by themselves.

B.To eat some fish outside the net.

C.To find the fish.

D.To show their intelligence.

4.What can we infer（推断）from the passage?

A.Some scientists can understand dolphin conversation.

B.Dolphins probably help fishermen by using their body language.

C.Dolphins help men because they like humans.

D.Dolphins can talk to humans about their age and feelings.

5.What's the main idea of the passage?

A.Dolphins can communicate with each other at birth.

B.Dolphins are social animals because they play together.

C.Dolphins are smart and they are like humans in some ways.

D.Dolphins help humans do many things like catching fish.