进行酸值测定煮沸5min的目的之一是将油中的（）用乙醇萃取出来。
A.无机酸
B.无机碱
C.有机酸
D.有机碱
参考答案：C
Professor Jordon is well known for his _____ into the habits of the common housefly.
A．examination
B．introduction
C．research
D．expression
抒情的途径有哪些？
