答案A． broke down “〔机械)坏了；(计划等)失败；(身体或精神)垮了；(感情控制不住)哭了”
the man was under so much stress that he finally broke down.
他背负着太多的压力以至于最后他身体(承受不了)垮了.
B.broke up “打碎,粉碎；(会议等)终止,结束”
C.broke out“爆发；突然发生；逃脱,逃走”
D.broke in“闯入；插嘴”