—The old man is ill. He to the hospital at once--Don’t worry. A doctor to come already

问题补充：

—The old man is ill. He to the hospital at once.

--Don’t worry. A doctor to come already.

A. must be sent , has asked

B. must send, have asked

C. must be sent, has been asked

D. must send, have been asked

答案：

A. must be sent , has asked

B. must send, have asked

(答案→)C. must be sent, has been asked

D. must send, have been asked

解析：句意：---这个老人生病了他必须马上被送到医院，----不要担心，医生已经被叫来了。 Must be done 表示含情态动词的被动语态，完成时的被动语态have been done 结构，根据题意可知选C