Answer:
The correct answer is option d.
Step-by-step explanation:
Barb’s aunt gave her $100 for her birthday with the condition that Barb buys herself something.
Barb narrows her options down to four choices: Option A, Option B, Option C, and Option D.
The cost of each option is $100.
She finally decides to go for option B.
In this situation, her opportunity cost for choosing option B will be the second-best alternative or the value of the option she would have chosen had Option B not been available.
Opportunity cost of an economic decision is the the cost of second best alternative that the person has to give up in the process of making decision.