[单选题]
What happens to the total reqfhro nn3 gm;6yn r-s3y(+fj.lativistic enelv5 5:9tsftks rgy of a speedy proton when its relativistic mass doubsf5kt 59vtsl :les?
A. It doubles.
B. It more than doubles.
C. It less than doubles.
D. It must increase, but it is impossible to say by how much.
