单项选择题
A.4.5% B.4.5‰ C.0.45% D.0.45‰
A.＞0.25% B.＞0.35% C.＞0.45% D.＞0.6%
A.≤0.25% B.≤0.15% C.0.25%—0.6% D.＞0.6%