"An objective of firms is to maximize profits". This statement:

a) has been proven by empirical testing to be always true.
b) is a normative statement and thus cannot be tested.
c) is an unrealistic assumption, and therefore of little use to economists
d) is an assumption used by economists to predict the behaviour of firms.
e) applies only to corporations

Ans: d) is an assumption used by economists to predict the behaviour of firms.