Which of the following italicized phrases indicates CAUSE?

A、 Why don't you do it for the sake of your friends?
B、 I wish I could write as well as you.
C、 For all his efforts, he didn't get an A.
D、 Her eyes were red from excessive reading.

【正确答案】 D

【答案解析】A中for the sake of your friends意为“为你朋友着想”，是主句的目的；B中as well as意为“和你一样”，表示比较；C中for all his efforts意为“尽管他非常努力”，表示让步，所以都不是正确答案。只有D项“由于过量阅读，她的眼睛都红了。”正确。