Correct Option: B

A shift in the demand curve is caused by a factor affecting demand other than a change in price. If any of these factors change then the amount consumers wish to purchase changes whatever the price. The shift in the demand curve is referred to as an increase or decrease in demand. A movement along the demand curve occurs when there is a change in price. This may occur because of a change in supply conditions. The factors affecting demand are assumed to be held constant. A change in price leads to a move
ment along the demand curve and is referred to as a change in quantity demanded.