题目

A:Do you know the woman under the tree? B: Sorry, I don’t know       .      A. how is she      B. what is she      C. who she is       D. where she is 答案：C细胞中染色体的主要成分是（  ）A．DNA和RNAB．DNA和蛋白质C．RNA和蛋白质D．DNA和酶