题目

My aunt would rather __________a bus _________ride a bike.A． to take, thanB． take, toC． take, thanD． taking, than 答案：C解析:略小麦抗锈病对易染锈病为显性。现有甲、乙两种抗锈病的小麦，其中一种为纯合子，若要鉴别和保留纯合的抗锈病的小麦，应选用下列哪种方法最简便易行(     ) A．甲×乙　　　B．甲、乙分别测交C．甲×甲，乙×乙　　D．甲×乙得F1再自交