24. The failure was a big_____to him, but he wasn't discouraged and soon got as enthusiastic as ever.
A
blow
B
issue
C
excuse
D
factor
句意为：这个失败对他来说是一个打击，但是他没有泄气，很快振作恢复了原来的热情。A.blow打击;B.issue问题;C.excuse借口;D.factor要素。所以选择A。
此题是词义辨析题，首先要明白句意，然后根据语境缺位补充词语。
单词意思不明。