B

Dolphins are famous tobe very bright. They are good at using whistles(哨声) as their language.

Dolphins usuallylive in groups. A group of dolphins near the beach usually has about 10members. Far away from the beach, groups can be much larger, with hundreds ofmembers. The members in a group are very friendly. They play with each other,talk to each other, and help each other. Dolphins often work together to fightagainst other animals, and find food.

Scientists watchdolphins in the Moreton Bay. Ina studies a group of dolphins for many years.She said, “When the dolphins live on natural food, I think it's more importantfor them to get on with others, or to learn from others, or to work with othersto get food.”

      It’s true that thesefriendly dolphins will continue to teach the scientists about their ways, asthey live in the clear waters of Moreton Bay. 

1.Dolphins are _______, they can use whistles to talk to each other.

A big

B smart

C scary

D lazy

解析：选B。细节理解题。由题干关键词use whistles跳读，找到目标信息；smart与bright可转换。

2.There are about _______ dolphins in a group near the beach.

A 10

B 30

C 80

D 100

解析：选A。细节理解题。由题干关键词near the beach跳读，在第二段找到目标信息about 10。

3.What is Ina?

A A nurse.

B A policewoman.

C A dolphin.

D A scientist.

解析：选D。细节理解题。由题干关键词Ina跳读，在第二段找到目标信息Scientists。

4.Why do dolphins work together?

A They want to play a game.

B They want to move far away.

C They want to find some food.

D They want to fight against people.

解析：选C。推理判断题。下文的find food实质上是海豚与其他动物打斗的原因，故答案为C。

5.Which of the following is TRUE?

A Scientists will stop watching the dolphins.

B Scientists will keep watching the dolphins.

C The dolphins will leave Moreton Bay.

D The dolphins learn much from the scientists.

解析：选B。推理判断题。由最后一段这些海豚继续教科学家关于它们的生活方式推断，科学家还 会在摩顿海湾观察海豚。