Speed of the Radiowaves, Gamma rays, X-rays and Microwaves are represented by $V_R, V_G, V_X$ and $V_M$ respectively in free space. Which option is correct?

$V_R>V_G>V_X>V_M$ $V_G>V_M>V_X>V_R$ $V_G>V_X>V_M>V_R$ $V_R=V_G=V_X>V_M$

$V_R=V_G=V_X>V_M$

The correct answer is Option (4) → $V_R=V_G=V_X>V_M$