单项选择题

Use 20g and distil at a rate of 2.5ml to 3.5ml Per minute for 5 hours.实验中蒸馏提取的速率是()

A.每5小时2.5ml一3.5ml
B.每小时2.5ml~3.5ml
C.每5小时12.5ml-17.5ml
D.每小时150ml--210ml
E.以上均不对