Option D
Every penny spent on a good or service must end up as someone's income so the total value of production in an economy equal the total value of income
Step-by-step explanation:
The circular flow model describes how cash flows through society. Cash moves from yielders to workers as payments and runs back to yielders as cash for products. Since all the value created must refer to someone in the class of a request on the value, the national product is equivalent to national income.
Each action in an economy comprises a buyer and a seller. Households spend cash for acquiring goods and services exhibited. Firms make a production settlement. Households are employing units which incorporate output created in the business firms