@moonydidit Yes, essentially they are very similar, but with a trade off, you are fully giving up one for the other. "The kid's may have a treat but they must pick between ice cream or candy". Cost-benefit looks at the detriment or benefit something may provide you or others. Two things can be true within a cost-benefit scenario, think of legislation. It can be true that a group of people benefit from higher taxes, like those that heavily utilize social programs or medicare, medicaid, etc. but the cost is that other classes will have to pay a larger share for things they can't utilize. So, in summary, trade-off is you can have one or the other, not both. Cost-benefit analyzes both sides and both things can be true at the same time.

@NobitaNobi Good points. But I think something I sometimes struggle to remember is that we only need the information provided in the stimulus or answers to answer a question. Both of your points, if they were addressed in the question material, would definitely require a look. But since we were only provided with teachers not wanting to relocate, then that is what we have to work with.