Answer: Option 'C' is correct.
Explanation:
As we know that
Oligopoly is a market structure that few sellers who can sell identical or differentiated products.
It needs heavy investment as well as heavy selling cost is also incurred.
whereas, Perfect competition and monopolistic competition both having large number of buyers and sellers and In perfect competition, products are identical or homogeneous whereas in monopolistic competition, products are differentiated .
Hence, Option 'C' is correct.