Answer:
Option B:
inferior good; elasticity is negative
Step-by-step explanation:
The income elasticity of demand is a measure of the rate at which a particular commodity is demanded, even after there is a change in the real income of the consumers.
It is a known fact that for inferior goods, once the real income of the consumers increases there is a higher tendency for them to switch to other premium commodities. Such goods are said to have a negative elasticity.
The income elasticity of demand can be calculated with this formula
percentage change in quantity demanded / percentage change in income.
If this gives a value that is less than 1, it means that the percentage change in the quantity of goods demanded is actually less than the percentage change in the income level of the consumers. Hence, the good is an inferior good. This is because when the consumers are earning more, they buy less of the product.