Concept:The size of an enterprise is measured by objective, quantifiable indicators such as capital invested, number of employees, output volume, and productive capacity.
Explanation:Among the given options, the amount of capital invested is a standard measure used to determine the size of an enterprise.
It allows comparison of both similar and different types of businesses.
Other accepted measures include the number of wage-earners employed, value of products, volume of output, power used, amount of raw materials consumed, and productive capacity of the plant.
The number of customers, length of operation, and type of work are not reliable indicators of enterprise size.
Capital invested directly reflects the scale and resources of the business.
Answer:C. Amount of capital invested.