Wang Tao ______ makes large pieces of metal art_____ makes smaller pieces for the home.
A:neither, nor
B:not only, but also
C:either, or
D:would rather, than
人胚胎在母体内发育的主要场所是( )
已知:化合物A+单质B→化合物C+单质D.试回答下列问题.
染色体和基因的正确关系是( )