Final answer:
Microeconomics is the branch of economics that analyzes the economic behavior of individual agents, focusing on their decision-making processes regarding purchases and utility maximization within budget constraints.
Step-by-step explanation:
The study of individual economic behavior is best described as microeconomics. This branch of economics focuses on the actions and decisions of particular agents within the economy, such as households, workers, and business firms. Microeconomics analyzes how individuals make choices about what goods and services to purchase within the confines of their budget constraints. These economic agents aim to maximize their total utility, which means achieving the highest level of satisfaction from their spending choices.