The first time a student played an online game, he played for 18 minutes.
Each time he played the game after that, he played for 12 minutes longer than the previous time.
After completing his 15th game, the total time he had spent playing these 15 games was
A. `186` minutes
B. `691` minutes
C. `1206` minutes
D. `1395` minutes
E. `1530` minutes