There exists uniform electric and magnetic fields in space. A particle is moving with a velocity $\overrightarrow v$ and suddenly a hollow metallic cube is enclosed around it. The change in force exerted on the particle is

Question

$\begin {array} {1 1} (a)\;q\overrightarrow v \times \overrightarrow B & \quad (b)\;q \overrightarrow E \\ (c)\;q ( \overrightarrow E+ \overrightarrow v \times \overrightarrow B) & \quad (d)\;Zero \end {array}$