Select the correct statements regarding macroeconomics.

(A) Macroeconomics deals with the aggregate economic variables of an economy.
(B) Macroeconomics emerged as a separate subject in the 1930s due to Keynes.
(C) Macroeconomics is a combination of households, firms, and the government sector only in open economy.
(D) Macroeconomics takes into account various inter - linkages which may exist between the different sectors of an economy.

Choose the correct answer from the options given below:

(A), (B) and (D) only

The correct answer is Option (1) → (A), (B) and (D) only

(A) Macroeconomics deals with the aggregate economic variables of an economy. Correct. Macroeconomics focuses on aggregates like National Income (GDP), total employment, aggregate demand, general price level, etc.

(B) Macroeconomics emerged as a separate subject in the 1930s due to Keynes. Correct. Modern macroeconomics, as a distinct field that studies economy-wide problems like the Great Depression, is generally considered to have started with the publication of John Maynard Keynes' The General Theory of Employment, Interest and Money in 1936.

(C) Macroeconomics is a combination of households, firms, and the government sector only in open economy. Incorrect. A model with only three sectors (households, firms, and government) is the definition of a closed economy model. An open economy model includes a fourth sector: the Foreign Sector (or rest of the world).

(D) Macroeconomics takes into account various inter - linkages which may exist between the different sectors of an economy.Correct. The study of macroeconomics heavily relies on the "Circular Flow of Income" model, which explicitly shows the inter-linkages (flows of goods, services, and money) between the household, firm, government, and foreign sectors.