The correct answer is: D. Monetary Theory
Irving Fisher was an American economist and statistician who made significant contributions to the development of economic theory, especially monetary theory and econometrics. He is best known for his work on the quantity theory of money, which states that the value of money is proportional to the quantity of money in circulation. Fisher also developed the Fisher equation, which is an equation that relates the nominal interest rate, the real interest rate, and the expected rate of inflation.
A. A Treatise on Money is a book by Irving Fisher that was published in 1911. The book is a comprehensive treatment of monetary theory and policy. It covers topics such as the quantity theory of money, the purchasing power parity theory, and the gold standard.
B. Policy against Inflation is a book by Irving Fisher that was published in 1936. The book is a discussion of the causes of inflation and the policies that can be used to control it.
C. The Making of Index Numbers is a book by Irving Fisher that was published in 1922. The book is a discussion of the theory and practice of index numbers. Index numbers are used to measure changes in prices, wages, and other economic variables.
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