对某患者静脉滴注单室模型药物,已知该药的t=1.9h,V=100L,若要使稳态血药浓度达到3μg/ml,则k等于
A.50.42mg/h
B.100.42mg/h
C.109.42mg/h
D.120.42mg/h
E.121.42mg/h
正确答案是C