Q.In which market form, does absence of competition prevail?

Absence of competition prevails under monopoly — option (b).

Market forms differ by the number of sellers and the degree of competition:

• Perfect competition — very many sellers; competition is at its maximum.
• Monopoly — a single seller of a product with no close substitutes and strong entry barriers. With no rival firms, there is no competition at all.
• Duopoly — two sellers; competition exists between the two. …