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Question $18$

Question $18$ of $20$

Elena's aunt gave her $$100$ for her birthday with the condition that Elena buys herself something. In deciding how to spend the money, Elena narrows her options down to four choices: Option A$,$ Option on Option B$.$ The opportunity cost of this decision is

a$.$ the value to Elena of the option she would have chosen had Option B not been available.

b$.$ the value to Elena of Options A$,$ C$,$ and D combined.

c$.$ $$100.$

d$.$ the average of the values to Elena of Options A$,$ C$,$ and D$.$