人类的生殖细胞、体细胞和受精卵中各含有多少个DNA分子（）A．生殖细胞23个体细胞46个受精卵23个B．生殖细胞46个体细胞46个受精卵23个C．生殖细胞23个体细胞46个受精卵46个D．生殖-生物

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