The correct answer is: B. The cost of advantage forgone.
Opportunity cost is the cost of an alternative that must be forgone in order to pursue a certain action. In other words, it is the value of the best alternative that is given up when a choice is made.
For example, if you choose to go to college, you are forgoing the opportunity to work full-time and earn money. The opportunity cost of going to college is the income you would have earned if you had worked instead.
Opportunity cost is an important concept in economics because it helps us to make rational decisions. When we are faced with a choice, we need to consider the opportunity cost of each option in order to make the best decision for us.
Option A is incorrect because it refers to the cost of taking advantage of an opportunity. Option C is incorrect because it refers to the cost of a particular situation. Option D is incorrect because it refers to the cost of speculative activities. Option E is incorrect because it refers to the minimum cost to carry out a project.