Final answer:
Microeconomics is the branch of economics that examines the functioning of individual markets and the behavior of individual economic agents like consumers and businesses, focusing on how they make decisions based on budget constraints and aiming to maximize total utility.
Step-by-step explanation:
The branch of economics that focuses on the behavior of individual decision-making units, such as households, workers, and business firms, is Microeconomics. This field of study aims to understand and analyze the economic choices and actions of these individual agents. When consumers make decisions about what goods and services to buy, they do so based on their budget constraints with the intention to maximize their total utility, or satisfaction. Microeconomics also examines how prices are determined in individual markets and how these prices influence the economic decisions of private actors.