Keith has a 2012 tax liability of $2,250 before taking into account his American Opportunity credit. He paid $2,700 in qualifying expenses, was a full-time student, was not claimed as a dependent on his parents' return, and his American Opportunity credit was not subject to phase out. What is the amount of his American Opportunity credit allowed?
A. $2,175
B. $1,500
C. $1,350
D. $2,700
E. $-0-