Which one of the following was used to determine the structure of the DNA molecule ( )

A．Transmission(透射) electron microscope

B．Scanning electron microscope

C．Differential centrifugatioin(差速离心)

D．X-ray crystallography

当事人正义的本义表现出的是（）。

A.内在的正义

B.内在的正直

C.外在的正义

D.外在的正直