单项选择题
Passage One
Questions 26 to 28 are based on the passage you have just heard.
26-28
Why do people want to save the whales There are two important reasons. One reason is that whales help to keep a balance between plants and animals. People have disturbed this balance. People get rid of their wastes by throwing them into the oceans and seas. People’s sewage and garbage increase the salt in ocean and sea water. The increased salt helps some plants and some very small animals to grow. These plants and animals can be harmful to fish. Whales eat an enormous amount of plants and animals that grow in very salty water. Therefore, whales are very important because they keep the ocean environment clean enough for fish. In addition, because fish provide necessary food for many people, people need whales, and many people want to save them.
A. Because whales keep a balance between plants and animals on land.
B. Because whales eat a lot of fish.
C. Because whales eat large amounts of garbage.
D. Because whales keep oceans clean for fish, and people need fish.