Two particles X and Y having equal charges, after being accelerated through the same potential difference, enter a region of uniform magnetic field and describe circular paths of radii R1 and R2 respectively. The ratio of masses of X and Y is -
(A) (R1/R2)1/2
(B) (R2/R1)
(C) (R1/R2)2
(D) (R1/R2)