when a bar of iron attracts other pieces of iron，it（）a magnet，and thus the attraction is called mangnetism.
A.will be acted as
B.acts as
C.is acted as
D.has been acted as
正确答案：acts as
when a bar of iron attracts other pieces of iron，it（）a magnet，and thus the attraction is called mangnetism.
A.will be acted as
B.acts as
C.is acted as
D.has been acted as
正确答案：acts as