Mark the letter A, B, C, or D on your answer sheet to indicate the cor

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

All of the plants now raised on farms _______ from wild plants. 

• A. A. had been developed
• B. B. have been developed
• C. C. having been developed
• D. D. was developped

"Trong câu có từ ""Now"" => Thể bị động ở hiện tại. 
Câu còn thiếu động từ => haven been developped."