A problem of price control is

Analyze the question: It asks for a problem (a negative effect) that comes from price control, which is when the government fixes the maximum or minimum price of goods.

Explain the concept: Price control usually takes two forms:

• Price ceiling (maximum price): set below the equilibrium price to protect consumers. It causes demand to exceed supply, so there are shortages.
• Price floor (minimum price): set above the equilibrium price to protect producers. It causes surpluses.

Solution: When a price ceiling creates a shortage, many buyers cannot get the goods at the official price. Some sellers then hide the goods and sell them illegally at higher prices. This is the black market. In Nigeria, we have seen this with petrol during scarcity, where fuel is sold above the official pump price.

Checking the options:

• A. Development of black-market: This is a well-known problem of price control. ✔
• B. Increased earning and higher profit: This is not a problem, and price control usually limits profit.
• C. Increase in employment: This is a benefit, not a problem, and it is not a direct effect.
• D. Increase investment: This is also a benefit. Price control tends to discourage investment.
• E. Redistribution of income: This is an aim or possible benefit of price control, not a problem.

Answer: The correct option is A, development of black-market.

Exam tip: When you see "problem of price control," think "shortage → black market → hoarding → illegal sales above the fixed price." Options describing benefits (more jobs, more investment, more income) are usually distractors.