Zero price elasticity of demand means

Price elasticity of demand measures the responsiveness of quantity demanded to a change in price [2]. It is calculated as the percentage change in quantity demanded divided by the percentage change in price [1]. When the price elasticity of demand is zero, the demand is classified as 'perfectly inelastic' [2]. In this specific state, the quantity demanded remains constant regardless of any fluctuations in price [2]. This implies that consumers are completely insensitive to price changes, often seen in absolute necessities where the same amount is consumed whether the price rises or falls significantly [2]. Graphically, this is represented by a vertical demand curve, indicating that for any change in price, there is absolutely no change in the quantity demanded [2]. Options 2, 3, and 4 describe relatively inelastic, elastic, and relatively inelastic scenarios respectively, but only option 1 defines a zero elasticity coefficient.

Sources

1. [1] Microeconomics (NCERT class XII 2025 ed.) > Chapter 2: Theory of Consumer Behaviour > 2.6 ELASTICITY OF DEMAND > p. 28
2. [2] https://www.investopedia.com/terms/p/priceelasticity.asp