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
They didn’t have the right visas. They couldn’t legally re-enter Thailand.

A. If they had had the right visas, they could have re-entered Thailand legally.

B. Had they had the right visas, they couldn’t re-entered Thailand legally.

C. Were they to have the right visas, they could re-entered Thailand legally.

D. If they had the right visas, they could re-entere Thailand legally.