A Key Determinant of the Price Elasticity of Supply Is

A key determinant of the price elasticity of supply is the time period under consideration.Which of the following statements best explains this fact?

A) Supply curves are steeper over long periods of time than over short periods of time.
B) Buyers of goods tend to be more responsive to price changes over long periods of time than over short periods of time.
C) The number of firms in a market tends to be more variable over long periods of time than over short periods of time.
D) Firms prefer to change their prices in the short run rather than in the long run.