The message is very important so it is supposed as soon as possible. A. to be sentB. to s

问题补充：

The message is very important, so it is supposed as soon as possible.

A. to be sent

B. to send

C. being sent

D. sending

答案：

(答案→)A. to be sent

B. to send

C. being sent

D. sending

解析：考查词组：be supposed to do应当做…,因为the message和send是被动关系，所以是不定式的被动，句意：这个信息很重要，应该尽快被送出去。选A。