The socks are so that they can't be mended any more.
A. used up
B. worn out
C. tired out
D. broken out
网友回答
A. used up
(答案→)B. worn out
C. tired out
D. broken out
解析：use up“用完，耗尽”；tire out“使十分疲劳”；break out“(战争、火灾等)突然发生，爆发”；wear out“穿破，用坏；克服；消磨；疲劳”。句意：这些袜子穿坏了，不能再补了。根据句意知应选B项。