Q.Explain the following in short.

Keynes focused on short-run equilibrium, so the answer is (d).

In the theories of employment and income topic of the Tamil Nadu HSC Commerce syllabus, the classical economists believed that in the long run the economy always tends towards full-employment equilibrium (Say's Law).

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Keynes's landmark contribution to economics is "The General Theory of Employment, Interest and Money" (1936) — option (d).

In the Tamil Nadu HSC Class-12 Economics syllabus (Theories of Employment and Income), John Maynard Keynes is the central figure of modern macroeconomics. His most influential book, The General Theory of Employment, Interest and Money (1936), founded Keynesian economics and gave the concept of effective demand and involuntary unemployment.

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Structural unemployment is a feature of a dynamic society, where continuous structural change in the economy makes some workers' skills or industries redundant.

Structural unemployment occurs because of fundamental changes in the make-up of the economy: introduction of new technology, shifts in consumer demand from one product to another, decline of old industries and rise of new ones, and mismatch between the skills workers have and the skills employers need.

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Keynes's major contribution is 'The General Theory of Employment, Interest and Money' (1936), so option (d) is correct.

John Maynard Keynes published 'The General Theory of Employment, Interest and Money' in 1936, which laid the foundation of modern macroeconomics and the theory of effective demand.

• (a) Capital — the work of Karl Marx. …