Under Conditions of Oligopoly Markets,firms Generally Don't Like to Compete

Under conditions of oligopoly markets,firms generally don't like to compete based on price.Why?

A) Because no producer has a cost advantage in doing so.
B) Because consumers rarely spend time making price comparisons between different brands.
C) Because competing on the basis of price can set off a price war among competitors and significantly reduce profits to the firm.
D) Because price competition is illegal in most states.