Which of the following cause demand of a product to increase? a) An increase in consumer's income b) An…

An outward shift (increase) in the demand curve for a normal product is caused by an increase in consumers' income (a), an increase in the price of substitute goods (which makes the product relatively cheaper) (b), and a favorable shift in consumer tastes and preferences toward the commodity (e). An increase in the price of complements or a proliferation of substitutes reduces demand for the product.