问题
单项选择题
在农业生产中，玉米利用杂交优势的途径是（）。
A.化学杀雄
B.人工去雄
C.自交不亲和性
D.雄性不育
答案
参考答案：B
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在农业生产中，玉米利用杂交优势的途径是（）。
A.化学杀雄
B.人工去雄
C.自交不亲和性
D.雄性不育
参考答案：B
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