I can hardly know _____ so complex a matter in such a case. [ ]

A. how to do with

B. what to do with

C. what to deal with

D. how dealing with

下表为3个不同小麦杂交组合及其子代的表现型和植株数目：据表分析，下列推断错误的是（）

A.6个亲本都是杂合子

B.抗病对感病为显性

C.红种皮对白种皮为显性

D.这两对性状自由组合