单项选择题

A.0.5g口服,每日4次,连续7d
B.0.5g口服,每日4次,连续10d
C.0.5g口服,每日4次,连续15d
D.0.5g口服,每日4次,连续20d
E.0.5g口服,每日4次,连续30d