The answer choices which should be included in the opportunity cost of buying the slip-ons is:
This is a term that is well known in the field of economics and is used to show the foregone alternative when a person is making a choice about a particular good or item.
With this in mind, we can see that Sean had to give up some things and these are what we can see as his opportunity cost even though they are not of monetary cost.
Therefore, the correct answer is option A
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