单项选择题
A.>2ng/m] B.>3ng/ml C.>4ng/ml D.>5ng/ml E.>10ng/ml
A.1岁之前 B.2岁左右 C.5岁 D.入学前 E.尽可能得早
A.0.5cm B.0.8cm C.1.Ocm D.0.7cm E.0.6cm