题目

阅读下列短文，从每题所给的四个选项（A、B、C或D）中，选出最佳选项 When I was small and my grandmother died, I couldn't understand why I didn't cry. But that night when my dad tried to cheer me up, my laughter turned to tears. So it came as no surprise to learn that researchers believe crying and laughing are controlled by the same part of the brain. Just as laughing has many health advantages, scientists are discovering that so does crying. Whatever helps us to reduce pressure is important to our emotional health, and crying seems to work well. One study found that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： 组合序号 杂交组合类型 子代的表现型和植株数目 抗病 红种皮 抗病 白种皮 感病 红种皮 感病 白种皮 一 抗病、红种皮×感病、红种皮 416 138 410 135 二 抗病、红种皮×感病、白种皮 180 184 178 182 三 感病、红种皮×感病、白种皮 140 136 420 414 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