Answer:
The correct answer is c) when a determinant of the demand for coffee other than the price of coffee changes.
Step-by-step explanation:
When the quantity demanded at each level of price changes, the demand curve shifts. This means that if there is a change in any determinant of the demand for coffee other than the price than the demand will shift either to the left or to the right depending on the positive or negative change in determinant. The determinants include income of the buyers, change in consumer taste, price of related goods, future expectation of price etc.
For eg-The demand curve for coffee will shift to the right when there is an increase in the price of it's substitute good like tea and vice versa.