Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

One of the men was lying on the ground after _______ down by a piece of rock. 

A. knocking 

B. being knocked 

C. knocking him 

D. was knocked 

mình cũng gửi người con gái mình thích một lời chúc tốt lành nhất