The radius of the circular path or helical path followed by the test charge q_o moving in magnetic field B with some velocity v is

• A

  $\frac{\mathrm{mvsin}\mathrm{\theta }}{{\mathrm{q}}_0\mathrm{B}}$

• B

  $\frac{\mathrm{mvcos}\mathrm{\theta }}{{\mathrm{q}}_0\mathrm{B}}$

• C

  $\frac{\mathrm{mv}}{{\mathrm{q}}_0\mathrm{B}}$

• D

  $\frac{\mathrm{mvtan}\mathrm{\theta }}{{\mathrm{q}}_0\mathrm{B}}$