Which of the following would not be studied in macroeconomics?

Which of the following would not be studied in macroeconomics?
A.The growth rate of the U.S. economy.
B.How a sharp increase in gasoline prices is likely to affect SUV sales.
C.The impact of government spending on the economy.
D.The causes of the Great Depression.
正确答案：How a sharp increase in gasoline prices is likely to affect SUV sales.