The correct answer is D. Keynes’s business cycle theory.
Keynes’s business cycle theory is the most commonly accepted principle of business cycle because it is the most comprehensive and well-supported by evidence. Keynes argued that business cycles are caused by fluctuations in aggregate demand, which can be caused by a variety of factors, including changes in investment, consumption, and government spending.
Hatrey’s business trade cycle theory is a theory of business cycles that was developed by Sir Roy Harrod and Sir Roy F. Harrod. The theory states that business cycles are caused by fluctuations in the rate of economic growth. The theory is based on the idea that the economy grows at a constant rate, but that this rate can be disrupted by changes in investment, consumption, and government spending.
Hicks’s business trade cycle theory is a theory of business cycles that was developed by John Hicks. The theory states that business cycles are caused by fluctuations in the rate of investment. The theory is based on the idea that investment is a key driver of economic growth, and that fluctuations in investment can lead to fluctuations in economic activity.
Hayek’s business cycle theory is a theory of business cycles that was developed by Friedrich Hayek. The theory states that business cycles are caused by fluctuations in the money supply. The theory is based on the idea that the money supply is a key driver of economic activity, and that fluctuations in the money supply can lead to fluctuations in economic activity.
Keynes’s business cycle theory is the most commonly accepted principle of business cycle because it is the most comprehensive and well-supported by evidence. Keynes argued that business cycles are caused by fluctuations in aggregate demand, which can be caused by a variety of factors, including changes in investment, consumption, and government spending. This theory is supported by a large body of empirical evidence, which shows that changes in aggregate demand are a key driver of business cycles.