已知豌豆红花对白花、高茎对矮茎、子粒饱满对子粒皱缩为显性,控制它们的三对基因自由组合。以纯合的红花高茎子粒皱缩与纯合的白花矮茎子粒饱满植株杂交,F2代理论上为( ) ①12种表现型 ②红花高茎子粒饱满:白花矮茎子粒皱缩为27:1 ③红花子粒饱满:红花子粒皱缩:白花子粒饱满:白花子粒皱缩为9:3:3:1 ④高茎子粒饱满:矮茎子粒皱缩为15:1 A.①②③ B.②③ C.③④ D.②③④ 18、
The growing speed of a plant
is influenced by a number of factors, _____ are beyond our control.
most of them
B. most of which C. most of what D. most of that