Proton , deuton and alpha particle of same kinetic energy are moving in circular trajectories in a constant magnetic field. The radii of proton , deuteron and alpha particle are respectively `r_(p), r_(d) and r_(alpha)`. Which one of the following relation is correct?
A. `r_(e ) lt r_(alpha) lt r_(p)`
B. `r_(e ) gt r_(p)=r_(alpha)`
C. `r_(e )lt r_(p) lt=r_(alpha)`
D. `r_(e ) lt r_(p) lt r_(alpha)`
