Competitive Market - Economics?

Question

Which of the following statements about a competitive market is incorrect?

A price floor makes the market less efficient.

Overproduction reduces consumer surplus and producer surplus.

Underproduction creates a deadweight loss.

A price ceiling makes the market more efficient.

Answer 1

A price ceiling makes the market more efficient.

If a price ceiling is ineffective (above the equilibrium price) it will have no effect on the efficiency of the market.  If it is below the equilibrium price, it will make the market less efficient, because fewer sellers will want to sell their product and fewer  buyers will have the opportunity to buy it.