TPO5閱讀第三篇39題中

題目：

TPO5閱讀第三篇39題中
B.一個以前不知道的Burgess Shale動物
For example（這不是現在知道）a well-known Burgess Shale animal called Sidneyia is a representative of a previously unknown （以前不知道的）group of arthropods (a category of animals that includes insects,spiders,mites,and crabs)" =
例如伯吉斯頁岩化石羣中的一種著名動物,Sidneyia,就是一種典型的以前還不爲人知的節肢動物（一種動物分類,它包括昆蟲、蜘蛛、蟎蟲和螃蟹）.
這不是以前不知道 的 正好嗎 爲什麼選C?

解答：

.「Sidneyia」 is an example of
　　○ a relative of Anomalocaris and Wiwaxia
　　○ a previously unknown Burgess Shale animal
　　○ an extinct member of a currently existing category of animals
　　○ an animal that cannot be assigned to any modern animal group
原文The Burgess Shale formation also has fossils of many extinct representatives of modern animal groups.For example,...
看到for example不要向後找,要向前找,知道這是舉得哪方面的例子.是舉得現代節肢動物在史前的已經滅絕的代表.他舉例子是爲了啥,B選項沒錯,但不是爲了B舉例子,是爲了C