第一节完形填空 (共10小题；每小题2分，满分20分)
阅读下面短文，掌握其大意，然后从21～30各题所给的A、B、C和D项中，选出最佳选项，并在答题卡上将该项涂黑。
Sea turtles have been on Earth for millions of years, but they may soon die out. The main   21   to them is people who kill them for food, according to Dr. Wallace J. Nichols of the University of California.
But the latest news may   22   turtle hunting: Dr. Nichols has found that sea turtles   23   a lot of pollution from the ocean. This pollution is unhealthy for both turtles and humans. It can cause __24__ damage to their bodies and lead to death. Research shows that many people get sick    and even die from eating sea turtle meat. 
In the US, most people have never eaten turtle. This is because turtles are   25   by the United States law, which makes it   26   to harm or kill these amazing animals. “But many people in other countries still eat them,” explains Nichols. “Our first   27   was to save turtles; now we must save   28   too.”
Davis said he also wants to send out a bigger   29   that we should protect the oceans. “The health of the ocean, animals in the ocean, and our own health are all   30  . A clean ocean is really good for us too because of the food we eat from there.”
21. A. doubt                  B. stream                      C. danger                    D. worry
22. A. accelerate              B. slow               C. improve          D. change
23. A. cause                  B. expand            C. absorb           D. reduce
24. A. accidental            B. occasional          C. unknown         D. serious
25. A. qualified             B. protected           C. restricted        D. produced
26. A. impossible          B. difficult            C. illegal            D. abnormal
27. A. goal                B. impression          C. difficulty         D. cost
28. A. Earth              B. ocean              C. people           D. animals
29. A. advertisement        B. message            C. sign             D. problem
30. A. concerned            B. disturbed           C. developed         D. connected