How will a reduction in the price of cotton (a key resource to make jeans) influence the market for blue jeans?

a. The cost of producing blue jeans will rise, and the supply curve for blue jeans will shift to the right.
b. The cost of producing blue jeans will fall, and the supply curve for blue jeans will shift to the left.
c. The cost of producing blue jeans will rise, and the supply curve for blue jeans will shift to the left.
d. The cost of producing blue jeans will fall, and the supply curve for blue jeans will shift to the right.