— Remember this, Paul. you work, grades you will get. — Thanks a lot, Mr. Miller. A. The hard; the good B. The harder; the best C. The harder; the better D. The hardest; the best 答案:C生物具有遗传多样性,遗传信息大多储存在DNA分子上,一个DNA分子的直径约为0.0000002cm.这个数量用科学记数法可表示为( )cm.