cost of Monique s decision is the time she can spend on other activities.

$8.$ The opportunity cost of Monique's decision is the value of the next$-$best alternative not chosen.

C$.$ The opportunity cost of volunteering at the shelter is the wages she gave up$.$

None of the above.

E$.$ All of the above.

The Agrizone Corporation invests $$19\mathrm{.}5$ million in a new inventory tracking system.

A$.$ The opportunity cost of Agrizone's decision is the value of leaving the money unutilized.

B$.$ The opportunity cost of Agrizone's decision is the value of the other investments it is pursuing at the same time.

C$.$ The opportunity cost of investing in a new inventory tracking system is any other projects Agrizone could have invested in$.$

D$.$ All of the above.

E$.$ None of the above.