The car ran into a crowd of middle school students, ________ to hospital immediately．

A.two of whom sent

B.two of them sent

C.two of whom are sent

D.two of them sending

答案及解析： B

考查定语从句与状语的区别。A项的语态不对，C项的时态不对。受伤的学生是被送往医院，故选B而不选D作状语。