radomize ul tag not working

this is probably an easy question for you guys but I'm very new to coding and can't figure out this. I have a code that I want to randomize the given choices in the questions, and I've found a script online that does that but it's not working. I don't know what the "// shuffle only elements that don't have "group" class $ul.find("li[class!='single_question', 'question', 'title', 'text']").each(function() { " means so I tried to put all id that I don't need to randomize in it but it's still not working. Can someone help me this please? Also is there anyway I can add choice "A", choice "B", choice "C", and choice "D" in front of each given options so even after the options(answers) are randomized, the A,B,C,D options will still be in order? Thank you. Here's the code:

HTML:

<div id="quiz_container">

        <ul class="quiz_container">

            <li class="single_question" data-question-id="1" data-correct-answer="1">
                <div class="question">
                    <h1 class="title">
                         P.1 Grammar Review
                    </h1>
                    <p class="text">
                        1. "What is your name__"
                    </p>
                </div>
                <ul class="options">
                    <li value="1">?</li>
                    <li value="2">.</li>
                    <li value="3">,</li>
                </ul>
                <div class="result"></div>
            </li>


<li class="single_question" data-question-id="2" data-correct-answer="b">
 <div class="question">
  <p class="text">
   2. "Do you like the banana__"
  </p>
 </div>
 <ul class="options">
  <li value="a">.</li>
  <li value="b">?</li>
  <li value="c">,</li>
 </ul>
 <div class="result"></div>
</li>
    </div>
    </body>
</html>

JS:

 $(document).ready(function(){

/*
 * shuffles the array
 * @param {Array} myArray array to shuffle
 */
function shuffleArray(myArray) {
    for (var i = myArray.length - 1; i > 0; i--) {
        var j = Math.floor(Math.random() * (i + 1));
        var temp = myArray[i];
        myArray[i] = myArray[j];
        myArray[j] = temp;
    }
    return myArray;
}

var $ul, $li, li_content, li_list;
// find all lists to shuffle
$("#quiz_container > ul").each(function() {
    $ul = $(this);
    li_list = [];
    // shuffle only elements that don't have "group" class
    $ul.find("li[class!='single_question', 'question', 'title', 'text']").each(function() {
       // add content to the array and remove item from the DOM
       li_list.push($(this).html());
       $(this).remove();
    });

    // shuffle the list
    li_list = shuffleArray(li_list);
    while(li_content = li_list.pop()) {
        // create <li> element and put it back to the DOM
        $li = $("<li />").html(li_content);
        $ul.append($li);
    }        
});

$("#contact_div").show();
  });


 $(document).on('click', '.single_question .options li', function(){

      // Save the question of the clicked option 
      question = $(this).parents('.single_question');

      // Remove If Anyother option is already selected
      question.find('.selected').removeClass('selected');

      // Add selected class to the clicked li
      $(this).addClass('selected');

      // selected option value
selected_answer_value = $(this).attr("value");

// Value of correct answer from '.single-question' attribute
      correct_answer_value = question.attr("data-correct-answer");
      correct_answer_text = question.find('.options').find("li[value='"+correct_answer_value+"']").text();

      if(correct_answer_value == selected_answer_value)
       result = "<div class='correct'> Correct ! </div>";
      else
       result = "<div class='wrong'> Correct answer is -> "+correct_answer_text+"</div>";

      // Write the result of the question
      $(this).parents('.single_question').find('.result').html(result);

      // Calculate the score
      score_calculator();

     });


     /**
      * It loops through every question and increments the value when "data-correct-answer" value and "option's value" are same
      */
     function score_calculator() {
      score = 0;
      $('.single_question').each(function(){
       question = $(this);
       if(question.attr('data-correct-answer') == question.find('.selected').attr("value")) {
        score++;
       }
      });
      $('.correct_answers').html(score);
     }