A positive charge \(\rm q\) is placed at \(\rm x = 0\) between two infinite metal plates placed at \(\rm x = −d\) and at \(\rm x = +d\) respectively. The metal plates lie in the yz plane.The charge is at rest at \(\rm t=0\), when a voltage \(\rm +V\) is applied to the plate at \(\rm – d\) and voltage \(\rm −V\) is applied to the plate at \(\rm x = +d\). Assume that the quantity of the charge \(\rm q\) is small enough that it does not perturb the field set up by the metal plates. The time that the charge \(\rm q\) takes to reach the right plate is proportional to

• A. \(\rm d/V\)
• B. \(\rm \sqrt d/V\)
• C. \(\rm d/\sqrt V\)
• D. \(\sqrt {{\rm{d}}/{\rm{V}}}\)