20.使用显微镜观察标本时,正确的方法是       A.两眼睁开,用

20使用显微镜观察标本时,正确的方法是

      A.两眼睁开,用左眼观察                      B.闭右眼,有左眼观察

C.两眼睁开,用右眼观察                      D.闭左眼,用右眼观察

答案

A

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