How does an increase in the price of an input affect the supply curve of a firm?
An increase in the price of an input leads to a rise in the cost of production for the firm. This increase in input prices causes the firm's marginal cost to rise at any given level of output, resulting in a leftward (or upward) shift of the Marginal Cost (MC) curve.
Since the supply curve of a firm is essentially a segment of the MC curve, the supply curve shifts to the left. As a result, at any given market price, the firm now supplies fewer units of output.
Explanation
The answer is derived from Section 4.5.2 'Input Prices' of the provided textbook context. It explains the chain of causality: input price rise -> production cost rise -> MC curve shifts left -> Supply curve shifts left -> lower quantity supplied at the same price.