The opportunity cost of doing or getting something is best and fully defined as:
A. The difference between the marginal cost and benefit of doing something
B. The materials used in doing or getting something
C. The value of the best alternative that is given up in order to do or get something
D. The money spent in doing or getting something

The correct answer is C. The value of the best alternative that is given up in order to do or get something.

Explanation: Opportunity cost literally means alternative thing forgone - meaning what is given up to get something (sacrifice). It is a concept used by economists to allocate limited resources for production, consumption, distribution and exchange of goods and services. Production of goods or services entails the creation of value. In other words, it gives a more understanding on how limited resources are allocated in order to satisfy the human insatiable desires.

For example, a student may be constrained with limited amount of pocket money, say $100 and the student wants to buy textbooks that cost $10 each or go for different outings going for $20 each. In this scenario, the student has different options: a) buy 10 textbooks and 0 outing b) buy 8 textbooks and a outing c) 6 textbooks and two outings d) 4 textbooks and three outings e) 0 textbooks and five outings. For the student to have any more of the other, he has to give up the other unit. What is given up is called opportunity cost.