One would expect that collusion among oligopolistic producers would be easiest to achieve in which of the following cases?

A very small number of firms producing a homogeneous product

Explanation:

An oligopoly is a corporate structure regulated by a few firms. It has been said that a market is highly competitive as divided by a few companies. Although only a few businesses rule, other small businesses will exist on the market as well.

Another oligopoly example is automotive manufacturing;

Ford (F), GMC and Chrysler are the main car manufacturers in the United states. In spite of smaller mobile operators, Verizon (VZ), Sprint (S), AT&T (T), and T-Mobile (TMUS) continue to be the industry's leading network.