Sorry to be late, but we were___

Sorry to be late, but we were____ for half an hour in the traffic.
A、put back
B、broken down
C、held up
D、kept off
【正确答案】：C
【题目解析】：本题考查短语动词辨析。put back 表示“推迟”；broken down表示“破坏”；held up表示“阻挡、拦截”；kept off表示“避开”。