【TPO一题求助】TPO2阅读中的一道题，在线

cnhomewy

大家好，TPO2里the origins of cetaceans有一道题不明白，答案是1，我选得3.希望大家帮忙解决一下。谢谢！
题目：10. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage?
Incorrect choices change the meaning in important ways or leave out essential information.
○Even though Ambulocetus swam by moving its body up and down, it did not have a backbone.
○The backbone of Ambulocetus, which allowed it to swim, provides evidence of its missing fluke.
○Although Ambulocetus had no fluke, its backbone structure shows that it swam like modern whales.
○By moving the rear parts of their bodies up and down, modern whales swim in a different way from the way Ambulocetus swam.
高亮部分：The structure of the backbone shows, however,
that Ambulocetus swam like modern whales by moving the rear
portion of its body up and down, even though a fluke was missing.

cnhomewy

已经解决，封帖！ 谢谢关注！