What does “perfectly inelastic supply” indicate about a good?

"Perfectly inelastic supply" indicates that the quantity supplied of a good remains constant regardless of price changes. This means that no matter how much the price rises or falls, the supplier will not alter the quantity they supply. This situation often occurs for goods that are unique or have fixed availability, such as artwork from a specific artist or land in a specific location, where the total quantity cannot be increased or decreased.

In this context, the other options do not accurately describe perfectly inelastic supply. The first option suggests that quantity supplied changes significantly with price, which contradicts the essence of inelastic supply. The third option implies a level of flexibility in supply response, which does not align with the concept of inelasticity. Lastly, the notion that changes in price have no effect on consumer purchasing is more relevant to demand rather than supply. Thus, the correct answer effectively captures the fundamental characteristic of perfectly inelastic supply.