[单选题]
What happens to the )qb.ium 9 y, xdfxyf.a/8,lew w eys-z3 k m,dafp3,a:total relativistic energy of a speedy proton when its relativis ms apk,z,aw-ed:fy3 3tic mass doubles?
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.