If peanut butter and jelly are complements, but peanut butter and tuna fish are substitutes,
A.
an increase in the price of peanut butter will increase the demand for jelly.
B.
an increase in the price of peanut butter will decrease the demand for jelly.
C.
an increase in the price of peanut butter will decrease the demand for tuna fish.
D.
a decrease in the price of peanut butter will increase the demand for tuna fish.