单项选择题
A.10 B.15 C.20 D.25
A.≥98% B.≥99% C.≥99.5% D.≥99.9%
A.0.5mg/kg-100mg/kg B.05mg/kg-1000mg/kg C.5mg/kg-100mg/kg D.5mg/kg-1000mg/kg