A) An increase in the price of a substitute good.
B) A decrease in consumer income, assuming the good is a normal good.
C) A decrease in the price of a complementary good.
D) A decrease in the price of the good.
For Explanation Click Here:
When the price of a complementary good (e.g., printers for computers) decreases, the demand for the original good (e.g., computers) increases. This is because consumers are more likely to purchase both goods together.