单选题 I got a new battery for my recorder only last week, but it seems to have ______ already.
A. worn out B. run down C. knocked off D. gone off

【正确答案】 B
【答案解析】run down用完；wear out穿破，用坏，疲劳；knock off撞倒，敲掉；go off去世，消失。