Which statements are correct for gel electrophoresis to separate $\text{DNA}$ fragments?
$(a)$ $\text{DNA}$ is a negatively charged molecule and so it is loaded on the gel towards the anode terminal.
$(b)$ $\text{DNA}$ fragments travel along the surface of the gel whose concentration does not affect the movement of $\text{DNA}$.
$(c)$ Smaller the size of $\text{DNA}$ fragments,larger is the distance it travels through it.
$(d)$ Pure $\text{DNA}$ can be visualized directly by exposing it to $\text{UV}$ radiation.

• A
  $a, c$ and $d$
• B
  $a, b$ and $c$
• C
  only $d$ is correct
• D
  only $c$ is correct