Concept:A budget line shows the maximum combinations of two goods a consumer can buy with a given income at fixed prices.Explanation:When a consumer’s money income increases while prices remain constant, the consumer can afford more of both goods.This means the budget line shifts outward from the origin.The shift is parallel because the relative prices of the goods have not changed.Therefore, higher income at constant prices expands the consumer’s purchasing options.Answer:A. Outward shift in the budget line.