Mark the letter A, B, C, or D on you...

Câu hỏi: Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.

A. I could have seen Susan off at the airport.

B. If only I had seen Susan off at the airport.

C. That I did not see Susan off at the airport escapes me now.

D. It suddenly dawns on me that I should have seen Susan off at the airport.