Final answer:
Microeconomics is the study of factors that affect the economic choices of individuals, households, and businesses. An economist who focuses on microeconomics would study how households and individuals spend their budgets, what combination of goods and services best fit their needs and wants, and how people decide whether to work, how much to save for the future, or whether to borrow to spend beyond their current means.
Step-by-step explanation:
Microeconomics is the study of factors that affect the economic choices of individuals, households, and businesses, as well as how changes in these factors can affect these decision makers, and how prices are determined in the market.
In this context, an economist who focuses on microeconomics would study how households and individuals spend their budgets, what combination of goods and services best fit their needs and wants, and how people decide whether to work, how much to save for the future, or whether to borrow to spend beyond their current means.
Therefore, out of the given options, an economist who focuses on microeconomics would be most likely to study income.