A:has been reached
B:had been reached
C:has reached
D:had reached
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淀粉、脂肪和蛋白质在人体消化道内被消化液消化的先后顺序正确的是( )
把下列句子译成现代汉语。
如图是植物细胞分裂、生长、分化的大致过程,请据图回答: