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A．KH₂PO₄、Na₂HPO₄、MgSO₄·7H₂O、葡萄糖、尿素、琼脂、水
B．KH₂PO₄、Na₂HPO₄、MgSO₄．7H₂O、葡萄糖、琼脂、水
C．KH₂PO₄、Na₂HPO₄、MgSO₄·7H₂O、尿素、琼脂、水
D．KH₂PO₄、Na₂HPO₄、MgSO₄·7H₂O、牛肉膏、蛋白胨、琼脂、水