Concept:Macroeconomics deals with the study of the whole economy using broad aggregates.Explanation:Broad economic aggregates include national income, total employment, general price level, and aggregate consumption.These variables describe the economy as a whole, not individual markets or single firms.Macroeconomics focuses on these large-scale totals and how they change over time.Therefore, the study of broad economic aggregates is called macroeconomics.Answer:A. Macro economics