十字丝中心与物镜光心的连线称为()。
A.横轴
B.竖轴
C.视准轴
D.旋转轴
参考答案:C
Many students believe the choice of their universities should _______ their own interests.
A.be based on
B.base on
C.be basing on
D.base at
维生素D缺乏性手足搐搦症的主要死亡原因()
A.脑水肿
B.喉痉挛
C.心力衰竭
D.呼吸衰竭
E.吸入性肺炎