Do you know many man-satellites space by our scientists since the middle of the

Do you know many man-satellites space by our scientists since the middle of the twentieth century?

A. have sent into　 B. were carried into　

C. have been sent into D. have been brought into

试题答案

C

从后面的“since ...”短语判断，应该用现在完成时。send sth. into意为“将……发射进入……”。