Which of the Following Would Shift the Supply Curve for Digital

Multiple Choice

Which of the following would shift the supply curve for digital cameras to the left?

A) An increase in the price of mobile phones (a substitute in production) .
B) An increase in consumer income (assuming that all digital cameras are normal goods) .
C) A decrease in the price of an input used to produce digital cameras.
D) A decrease in the number of firms that produce digital cameras.