What Is the Opportunity Cost of Going to College

What is the opportunity cost of going to college?

A) the total spent on food, clothing, books, transportation, tuition, lodging, and other expenses
B) the value of the best opportunity a student gives up to attend college
C) zero for students who are fortunate enough to have all of their college expenses paid by someone else
D) zero, since a college education will allow a student to earn a larger income after graduation