棉花系统育种程序中选择单株是基础,组织()是关键。
A、审定、示范、推广
B、三级试验(株行、品系预备、品系比较)
C、繁殖、审定、推广
D、繁殖、示范、推广
参考答案:B
A new movie Sacrifice came out last year, Ge You played adoctor saved an orphan at the cost of his own baby.
A.in which; who
B.when; who
C.on which; by whom
D.where; whom
建筑面积大于()m2的人防工程内地下商场应设置自动喷水灭火系统。
A.200
B.300
C.500
D.800