题目

下列关于生物生殖发育的描述中正确的是 A．蚊、蝇、蝗虫、蟋蟀进行不完全变态发育 B．所有鸡卵都能孵化出小鸡                                                                                                                                                                                                                                                                                                                                                                                                                        C．人的卵细胞在输卵管内受精，到达子宫后，才开始进行细胞分裂 D．嫁接成活的关键是接穗与砧木的形成层紧密结合 答案：D

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