Carolyn Bates is a junior in college studying economics. She has created a new software application that applies the four principles of economic decision making to any potential decision that a user faces. She is considering leaving school after this academic year to pursue further development of her app. Carolyn should consider all of the following costs when calculating the opportunity costs of leaving college EXCEPT the:_______________

a. potential fame that could come from creating a useful app.
b. cost of supplies and the technology fees she paid during the first three years of college.
c. potential forgone profits from selling her app.
d. None of the answers
e. time she will spend studying instead of working on the app.