Final answer:
A shift in demand from D1 to D2 would not be caused by a change in price. The shift is caused by other factors such as changes in consumer income, consumer preferences, or market competition.
Step-by-step explanation:
In economics, a shift in demand from D1 to D2 indicates a change in demand due to factors other than the good's own price. Therefore, a change in the price of the good is not the cause of the shift (option a). Other factors such as changes in consumer income, consumer preferences, and market competition could cause a shift in the demand curve.
For instance, an increase in consumer income often leads to an increase in demand for goods, shifting the demand curve to the right (D2). Similarly, changes in consumer tastes or preferences can affect demand. For example, if consumers suddenly develop a strong preference for electric vehicles, the demand for these vehicles would increase, shifting the demand curve to the right. Lastly, market competition could also affect demand. If a competitor product becomes more popular or cheaper, the demand for the product in question may decrease, causing a leftward shift in the demand curve.
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