We here on time but we were caught in a traffic jam.
A. must have arrived
B. could have arrived
C. need have arrived
D. should have arrived
网友回答
A. must have arrived
(答案→)B. could have arrived
C. need have arrived
D. should have arrived
解析：B 考察虚拟语气，句义：我们本来能够准时到达，可是我们遇见了交通堵塞了。Could have arrived本来能够到达，却没有到达。符合语境。故B正确。