题目

You wake up in the morning，the day is beautiful and the plans for the day are what you have been looking forward to for a long time．Then the telephone rings，you say hello, and the drama starts．The person on the other end has a depressing(令人沮丧的) tone in his voice as he starts to tell you how terrible his morning is and that there is nothing to look forward to．Yon are still in a wonderful mood? Impossible!    Communicating with negative people can wash out your happiness．It may not change what you think，but communicating long enough with them will make you feel depresse在一个细胞周期（间、前、中、后、末期）中，下列现象最可能发生在同一时期的是 A．DNA复制和中心粒的复制　 B．着丝点的分裂和细胞质分裂 C．细胞板的出现和纺锤体的形成 D．染色体数加倍和染色单体形成