---You part in the party on time.
--- Sorry, I was delayed by the accident.
A. are supposed to take
B. have supposed to take
C. are supposed to have taken
D. supposed to take
网友回答
A. are supposed to take
B. have supposed to take
(答案→)C. are supposed to have taken
D. supposed to take
解析：考查固定搭配以及不定式用法。固定搭配be supposed to do sth应该做某事；如果不定式的动作发生在谓语动作之前，就使用不定式的完成式来表示这个已经完成的动作。句意：—你本应该准时参加这个聚会的。—对不起，我遇见了交通堵塞。故C正确。