Answer:
The answer is: 3. The quantity of available rental housing units falls
Explanation:
Rent control is a type of price ceiling, where the price of a product is artificially lowered below the equilibrium price.
Whenever a price ceiling is introduced, the quantity supplied of products or services will decrease. That happens because as the price of a product increases, suppliers are willing to offer a larger quantity of that product. But if the price of a product decreases, suppliers will be willing to offer smaller quantities of that product. (Law of Supply).