When considering factors that shift demand curves, all of the following will decrease demand except . Select the correct answer below:
1. a drop in the price of substitutes
2. a rise in income (for an inferior good)
3. a rise in income (for a normal good)
4. all of these factors decrease demand

All the options above will decrease demand except a rise in income (for a normal good). Option 3.

Explanation: The demand for normal goods and a rise in income are directly related, meaning that whenever there is a rise in income level, it will lead to a rise in demand for normal goods.

For example, the demand for household appliances will increase with an increase in income, because household appliances are normal goods.

3) a rise in income (for a normal good)

Explanation:

A rise in the customers' level income level will shift the demand curve of a normal good to the right, which means that the quantity demanded of a product or service will increase at every given price. This should cause the equilibrium quantity and the equilibrium price to increase.

A normal good is a good whose demand increases as the income level of its consumers increases.