Concept:The smaller the proportion of income spent on a commodity, the lower its price elasticity of demand.Explanation:A commodity that takes an insignificant proportion of a consumer's income is usually a low-cost item.A change in its price only causes a negligible change in the consumer's overall budget.As a result, the consumer does not significantly alter the quantity demanded when the price changes.This makes the demand for such a commodity price inelastic.This concept is about responsiveness to price, not about changes in income.Answer:B. price inelastic