Mark the letter A, B, C or D to indi...

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

A. Only if they had finished one project did they start working on the next.

 B. Had they finished one project, they would have started working on the next. 

C. Hardly had they finished one project when they started working on the next. 

D. Not until did they start working on the next project then they finished one.