Which pair of market structures provides firms with the greatest ability to finance R&D out of retained earnings?

A) Oligopolists and pure monopolists.
B) Pure competitors and pure monopolists.
C) Pure competitors and monopolistic competitors.
D) Monopolistic competitors and pure monopolists.

Oligopolists

Firms in a market structure dominated by a small number of large companies, having significant control over their industry's prices and policies.

Pure Monopolists

Firms that are the sole providers of a product or service in a market, facing no competition.

Retained Earnings

The portion of a company's profits that is held or retained and not paid out as dividends to shareholders, often used for investing in business growth.