用数字0，1，2，3，4，5组成没有重复数字的四位数．

X，Y，Z，R是短周期主族元素，X原子最外层电子数为电子总数的 $\frac{2}{3}$ ，Y原子最外层电子数是内层电子数的3倍， Z元素的单质常温下能与水反应产生氢气，R原子的核外电子数是X原子与Z原子的核外电子数之和。下列叙述正确的是（    ）

    I have1good friend and his name is Jack. Here are his2about his life in twenty years. Jack will be a policeman in twenty years because he thinks it's an exciting job. He will live and work3Beijing, because it's a very beautiful city and he likes it very much. He4taller and stronger and he will have short straight hair. In his free time, he will play5sports to6. He will play tennis every day and he will go swimming and skating on weekends. He will7smart clothes like uniform. Jack will have a happy family. Maybe he will have two8. They will be lovely and cute and he will love them very much. Now he9and tries his best10his predictions come true.

某果农让同一棵桃树的不同枝条上结出了三种不同口味的桃子，他采用的繁殖方式是（　　）