The law of demand will not hold when

1. Analyze the question The law of demand says that, ceteris paribus (other things being equal), when the price of a good rises, the quantity demanded falls, and when the price falls, the quantity demanded rises. The question asks when this relationship breaks down. In other words, it asks for an exception to the law of demand.

2. Explain the concept Common exceptions to the law of demand include:

• Giffen goods: inferior staples where a price rise leads to more being bought.
• Veblen (prestige) goods: goods bought for status, so a higher price makes them more desirable.
• Rare commodities (antiques, art, rare gems): scarcity and exclusivity mean people want them more as the price rises.
• Expectation of future price changes: speculative buying.

3. Work through the options

• A. Normal goods: These obey the law of demand. A price rise reduces quantity demanded. This is not an exception.
• B. Size of population changes: This shifts the whole demand curve (a change in demand). It does not break the price-quantity relationship.
• C. Rare commodities: These are an exception. Collectors treat a higher price as a sign of greater value or prestige, so demand may rise as price rises.
• D. Incomes of consumers increase: This is a non-price determinant that shifts the demand curve. It is not an exception to the law.

4. Answer The correct option is **C. rare commodities are involved.

5. Exam tip Remember the exceptions with "G-V-R-E": Giffen goods, Veblen goods, Rare items, Expectations. Also, changes in income, population, or tastes shift the demand curve. Only a change in the good's own price moves along it. WASSCE often tests this difference.