I tried adding the icon by using the
::after
selector, of
 option:checked
but that didn't work, apparently, they don't have an after (maybe, I tired *::after that didn't caused any change)
<select>
  <option>
    abc
  </option>
  <option>
    bc
  </option>
  <option>
    c
  </option>
</select>
<style>
option:checked::after {
content:'\2713';
}
</style>
