(04上海卷)马和豚鼠体细胞具有相同数目的染色体,但性状差异很大,原因是 A.生活环境不同 B.DNA分子中碱基对排列顺序不同 C.DNA分子中碱基配对方式不同 D.着丝点数目不同 答案:答案:B11.-You should say sorry to your father for the mistake you made,Tom.-I don't _______ to meet his eyes.What if he gets angry with me?( )A.needB.haveC.dareD.Refuse