Colin just graduated from college with a degree in engineering. He decided to create a personal budget to help him pay all of his bills and still save money for retirement. His first monthly paycheck, after taxes, was $3,900. He had the following expenses. Fixed expenses (rent and monthly bills) were $2,535. He spent $507 for food. Entertainment cost him $390. The remainder of his paycheck Colin placed in a savings account for retirement. What percent of his paycheck did he save for retirement?
A. 12%
B. 22%
C. 17%
D. 7%