Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions.

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