The value of the best alternative activity that is forgone is known as the:a. marginal cost. b. marginal benefit. c. explicit cost. d. opportunity cost.

d. opportunity cost.

Explanation:

Opportunity cost is the cost of choosing some alternatives over the other alternatives.

It is the benefit that is sacrificing from choosing the best alternative among the available alternatives.

The formula to compute the opportunity cost

Opportunity cost = Not choose alternative - choose alternative

The example is an implicit cost