An oligopoly is characterized as an industry in which:

A) there are few firms,each producing a differentiated or similar product.
B) there are many firms,each producing a similar product.
C) all market participants are price takers.
D) only one firm produces a very differentiated product.

An oligopoly is an industry in which there are few firms, each producing a differentiated or similar product. This means that the market power is concentrated among a few firms, and they often engage in strategic behavior such as price collusion or non-price competition. Option B describes a perfectly competitive market, Option C describes a market with no market power, and Option D describes a monopolistic market.