An electron and a proton of equal linear momentum enter in a direction perpendicular to a uniform magnetic field. If the radii of their circular paths are $r_e$ and $r_p$ respectively,then $\frac{r_e}{r_p}$ is equal to - (mass of electron $= m_e$,mass of proton $= m_p$)

• A
  $\left[\frac{m_p}{m_e}\right]^{\frac{1}{2}}$
• B
  $\frac{m_e}{m_p}$
• C
  $\left|\frac{m_e}{m_p}\right|^{\frac{1}{2}}$
• D
  $1$