The graph to the right represents Mario's mile time in minutes.y, based on the number of hours he spends training in hours, X. What conclusion can you make?
A. Mario's fastest miles is 1/2 of an hour
B. Mario can run a 2 minute mile after an hour of training
C. Mario's miles time goes down 1 min for every 2 hours of training
D. Mario's mile time goes down 2 mins for every 1 hour of training