The two correct answers that would cause a shift in the demand curve for a given good are:
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Income - Changes in consumer income can affect the demand for goods. For normal goods, an increase in income typically leads to an increase in demand, while for inferior goods, an increase in income typically leads to a decrease in demand.
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Price of related goods - The demand for a good can be affected by the price of related goods, which includes substitutes and complements. For example, if the price of a substitute good increases, the demand for the original good may increase, and if the price of a complement good increases, the demand for the original good may decrease.
The other options (number of sellers, price of the good, input prices) primarily affect the supply curve rather than the demand curve.