Final answer:
An increase in income leads to a rightward shift of the demand curve for a normal good, due to its positive income elasticity of demand.
Step-by-step explanation:
In economics, when we discuss the impact of changes in income on the demand for goods, we focus on how these changes affect the demand curve for normal and inferior goods. For a normal good, an increase in income will result in the demand curve shifting to the right. This is because a normal good has a positive income elasticity of demand, meaning as consumers' income rises, they are more likely to buy more of these goods. The magnitude of the shift in the demand curve depends on the income elasticity of demand—if it's high, the shift will be larger.
Conversely, for an inferior good, which has a negative income elasticity of demand, an increase in income would lead to a leftward shift of the demand curve. However, the question specifies that 'x' is a normal good, so the appropriate answer to the question is that an increase in income will shift the demand curve for 'x' to the right.