The distinction between a change in demand and a change in quantity demanded is best made by saying that:
A. a change in quantity demanded is caused by a change in price and a change in demand is caused by a change in other factors besides price.
B. a change is demand is caused by a change in price and a change in quantity demanded is caused by a change in other factors besides price.
C. a change in quantity demanded causes a change in demand.
D. a change in both quantity demanded and demand is caused by a change in price.