Contrary to microeconomics, in macroeconomics we think big. We consider, in macroeconomics, not only the supply of and demand for bread in a particular market, but the supply of and demand for all goods and services produced in the economy; not only the price of bread but the average price of all products in the economy; not only the consumption of a single person or family, but the overall consumption of all the people or families in the economy; not only the investment of a single automobile factory, but investments of all businesses in the economy as a whole. Macroeconomics is not only interested in the determinants of these large scale variables, but also mutual relationships among them and the meaning of changes they display in time. Since choice A is related to microeconomics.