Collusion is A. necessary for firms to raise money by borrowing from investors or from banks in order to fund research and development required to develop new products. B. legal under U. S. antitrust laws if the intent is to increase competition. C. an agreement among firms to charge the same price or otherwise not to compete. D. common among monopoly firms.

The correct answer is the option C: an agreement among firms to charge the same price or otherwise not to compete.

Explanation:

To begin with, the name of "collusion" refers to an economy concept that focus on the situation where two or more companies decide to work together ilegally by taking a same strategy such as pricing the goods with a same amount so in that order the limit or at least intent to restrict the competion so in that way those firms can keep a piece of the market for themselves. It is consider ilegally in the countries because it is an disadvantage for the competition.

the correct answer is b.)