人的体细胞中的染色体数为23对46条,则其受精卵、精子中染色体的数量分别为( )
A.23条 46条
B.46条 46条
C.23条 23条
D.46条 23条
答案:D
It is global warming, rather than other factors,_____ the extreme weather.
A.that have led to
B.which has caused
C.which are causing
D.that has led to
铺放土工织物导渗沟时,保护土层厚度应为多少?