The difference between a change in supply and a change in the quantity supplied is that the latter is a. conditional upon a change in the former, but not vice versa. b. shown as a shift in the supply curve while the former is displayed graphically as a movement along a supply curve. c. determined by the willingness of producers to sell while the former is set by the ability of firms to produce. d. produced by a change in the product's own price while the former is caused by a variety of variables other than the product's price.