docs: def has_chosen(state, correct, msgs):
      """Verify exercises of the type MultipleChoiceExercise
  
      Args:
          state:    State instance describing student and solution code. Can be omitted if used with Ex().
          correct:  index of correct option, where 1 is the first option.
          msgs  :    list of feedback messages corresponding to each option.
  
      :Example:
          The following SCT is for a multiple choice exercise with 2 options, the first
          of which is correct.::
  
              Ex().has_chosen(1, ['Correct!', 'Incorrect. Try again!'])
      """
  
      ctxt = {}
      exec(state.student_code, globals(), ctxt)
      sel_indx = ctxt["selected_option"]
      if sel_indx != correct:
          state.report(Feedback(msgs[sel_indx - 1]))
      else:
          state.reporter.success_msg = msgs[correct - 1]
  
      return state