单选题 Once considered to be in danger of ______ , whales now enjoy themselves in the ocean thanks to the wildlife conservation program.
A. withdrawal
B. resolution
C. decadence
D. extinction

【正确答案】 D

【答案解析】初级问题在托业考试中，凡是与动物相关的题目就会反复出现这样的词语：in danger of extinction意为“面临灭绝的危险”；endangered species是“有(绝种)危险的物种”；extinct species是“已经灭绝的物种”。
[高频词语] once considered 曾被认为…… thanks to 幸亏