The correct answer is option 4, cyclical unemployment.

Cyclical unemployment refers to a type of unemployment that occurs as a result of the economic cycle. It is caused by fluctuations in the overall demand for goods and services in an economy. When the economy experiences a downturn or recession, the demand for goods and services decreases, leading to a decrease in production and a subsequent decrease in employment opportunities. This type of unemployment is temporary and directly related to the state of the economy.

Seasonal unemployment, option 1, refers to unemployment that occurs in industries that are affected by seasonal factors, such as agriculture or tourism. This is not the same as inadequate productive capacity in the economic system.

Structural unemployment, option 2, is caused by a mismatch between the skills required by employers and the skills possessed by available workers. It is not directly related to inadequate productive capacity.

Disguised unemployment, option 3, refers to a situation where individuals are employed but are not contributing to the productive capacity of the economy. It is more commonly seen in agrarian economies and is not directly related to inadequate productive capacity.

Therefore, based on the provided options, the correct answer is option 4, cyclical unemployment.