题目

豌豆种皮灰色对白色为显性，子叶黄色对绿色为显性。豌豆甲自交全部为灰种皮黄子叶，豌豆乙自交全部为白种皮绿子叶。现将甲的花粉授到乙的柱头上，下列叙述正确的是 A.杂交所得种皮全呈白色，子叶全呈黄色  B.杂交所得种皮全呈白色，子叶全呈绿色 C.杂交所得种皮全呈灰色，子叶全呈绿色  D.杂交所得种皮全呈灰色，子叶全呈黄色  ________ the clouds, you would find the airplane in the sky easily. [　　] A．Were it not for B．If it had not been for C．If it were not D．Had it not been for