D
25. The sea otter is well adapted at its marine existence, with ears and nostrils
A B C
that can be closed under water.
D
狗屎
26. Petroleum, which currently makes up about four-tenths of the world's energy
A
production, supplies more commercial energy than any another source.
B C D
27. Someone may refuse to recognize the seriousness of an emotionally threatening
A B C
situation and perceive as less threatening.
D
28. Through experiments with marine organisms, marine biologists can increase
A B
our knowledge of human reproductive and development as well as our understanding
C
上一页 [1] [2] [3] [4] [5] [6] [7] 下一页
