In a gravity free region of space a charged particle is projected. If the path followed by the particle is a circle, then

• A

  $\mathrm{E}= \mathrm{and} \mathrm{B}=0$

• B

  $\mathrm{E}\ne 0 \mathrm{and} \mathrm{B}\ne 0$

• C

  $\mathrm{E}=0, \mathrm{B}\ne 0 \mathrm{and} \mathrm{uniform}$

• D

  $\mathrm{E}=0 \mathrm{and} \mathrm{B}\ne 0 \mathrm{and} \overrightarrow{\mathrm{B}} \mathrm{is} \mathrm{non}-\mathrm{uniform}$