Nevaeh Decides to Spend Four Hours Playing Video Games Rather

Nevaeh decides to spend four hours playing video games rather than attending her classes. Her opportunity cost of playing video games is

A) the value of the knowledge she would have received had she attended her classes.
B) the $40 she could have earned if she had worked at her job for those four hours.
C) the value of her time playing video games minus the value of attending classes.
D) nothing, since she valued playing video games more than attending classes.