单项选择题
A.口腔 B.胃 C.肝 D.小肠 E.结肠
A.0.8~1.0g B.1.0~1.5g C.1.5~2.0g D.2.0~4.0g E.5.0~8.0g
A.1%~2% B.5%~10% C.12%~14% D.15%~20% E.20%~30%