You Are Shopping at the Local Mall with an $80

You are shopping at the local mall with an $80 gift certificate.Only three items catch your attention.The items include a Justin Bieber sheet set,a remote control helicopter,and an "Amazing Ab Belt." You would be willing to give up $60 for the sheets,$70 for the belt,and $80 for the helicopter.Knowing this,you decide to purchase the helicopter.The opportunity cost of the helicopter was:

A) $130, the combined value of the alternatives forgone.
B) $80, the amount of the gift certificate spent.
C) $70, the value of the ab belt.
D) $60, the value of the sheets.