Ⅰ.阅读理解(共15小题，每小题2分，共30分)
阅读下列短文，从每题所给的四个选项(A、B、C、D)中，选出最佳选项。
A
Two dolphins race around in a big pool in the Ocean Park.The smaller dolphin，Grace，shows off a few of her tricks，turning around and waving hello to the crowd.The most amazing thing about her，however，is that she's even swimming at all.She doesn't have a tail.
