They believe a single gunman carried out the attac...

Câu hỏi: They believe a single gunman carried out the attack.

A. The attack’s is believed to have carried out a single gunman

B. A single gunman is believed to have carried out the attack

C. It is believed to be carried out the attack by a single gunman.

D. It is believed that the attack has been carried out by a single gunman.