The growing speed of a plant is influenced by a number of factors, are beyond our control.
A. most of them
B. most of which
C. most of what
D. most of that
网友回答
A. most of them
(答案→)B. most of which
C. most of what
D. most of that
解析：考查定语从句：先行词是a number of factors,定语从句用most of+which引导，句意;一个植物的生长速度受很多因素影响，其中大部分不是我们控制的。选B。