Which of the following is a non-price determinant that can shift the supply curve?

• A. Input prices
• B. Price of the good
• C. Consumer income
• D. Prices of related goods

Answer: (A)

Supply can shift due to factors other than the price of the good itself. Input prices affect production costs directly: when the prices of inputs rise, producing the good becomes more expensive, so producers are willing to supply less at every price, shifting the supply curve to the left; when input prices fall, supply shifts to the right. The price of the good causes movement along the supply curve rather than a shift. Consumer income and prices of related goods influence demand, not supply.