Answer:
C. Consumer income
Explanation:
Consumer income is the variable that will cause the demand curve to shift.
Quantity demanded is the amount of goods and services that a consumer is willing to buy at given price.
Demand curve is the curve when plotted on the graph, it show the relationship between price and quantity demanded.
Factors affecting the quantity demanded by the customer are:
As per the law of demand, consumer income affect the quantity demanded as demand of inferior goods decrease with the increase in the income of consumer, however, demand of superior goods or branded goods increases with the increase in the income of consumers, which also cause the demand curve to shift.