Answer:
The correct option is d. Market control by a few large firms.
Step-by-step explanation:
An oligopolistic market structure can be described as a market structure in which there is a small number of large firms, and none of the large firms can prevent the other large firms in the market from wielding great power.
An oligopolistic market structure is there a market that is dominated and controlled by by a few large firms.
Therefore, the correct option is d. Market control by a few large firms.