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. She has been listening to the radio at 7.30.

B. She had been listening to the radio since 7.30

C. She has been listening to the radio after 7.30

D. She had been listening to the radio by 7.30