Final answer:
A trade-off occurs when one benefit is given up in order to gain another. The opportunity cost represents the most desirable alternative that was given up in the decision-making process.
Step-by-step explanation:
A trade-off occurs when one benefit is given up in order to gain another. This means that when we make a decision, we often have to sacrifice something else. The alternative that we sacrifice in the decision-making process is called the opportunity cost. The opportunity cost is the most desirable alternative that was given up.
For example, if you choose to go to the movies instead of seeing a concert, the trade-off is giving up the chance to go to the concert. In this case, the opportunity cost is the enjoyment and experience you would have had at the concert.
Therefore, the correct answer to the question is b) Trade-off.