Game theory is used in a number of areas in economics to analyze strategic behavior.What is the primary reason

Game theory is used in a number of areas in economics to analyze strategic behavior. What is the primary reason

that it is used in analyzing oligopoly type market structures?

Select one:

a. The firms are producing differentiated products

b. In oligopoly, the decisions of each firm affect the other firms. 

c. The demand curve facing the oligopolistic firms is perfectly inelastic

d. The demand curve the oligopolistic firm faces is downward sloping

e. The firms are producing a similar product