Html select form - how to trigger “dynamically generated option”

See more:

Javascript

HTML

MySQL

I have a HTML form along with a script, which automatically triggers the default "option" (option values hard-coded).

I also have a stand-alone script, which creates the choices of "options" dynamically, based on a specific column values in MySQL.

Problem: When selecting from the drop-down list from the dynamically generated list, it does not "trigger" anything (nor manual, nor automatic, manual would be just fine in this case)

The form which auto-triggers the default "option":

<form>
    <select name="fruit" onchange="showFruit(this.value)">
        <option>Choice:</option>    
        <option value="1">Yellow Fruit</option>
        <option value="2">Red Fruit</option>
    </select>
</form>

<script>
    window.onload = function () {
        var el = document.getElementsByName('fruit')[0];
        el.value = 1; //Set default value
        el.onchange(); //trigger onchange event
    }

    function showFruit(val) {
        alert(val);
    }
</script>

And the code which generates and displays the dynamically created list from a specific MySQL column:

<? $connect = mysqli_connect('localhost', '*', '*', '*');   
 $sql="SELECT DISTINCT(fruit_name) AS fruit_name FROM fruit ORDER BY fruit_name ASC"; 
 $result  = mysqli_query($connect, $sql);  

 if(mysqli_num_rows($result) > 0){  
 $select= '<select name="select">';
 while($rs = mysqli_fetch_array($result)){  
      $select.='<option value="'.$rs['id'].'">'.$rs['fruit_name'].'</option>';
  }
}
$select.='</select>';
echo $select;

How can I have the onload function to attach to the dynamically generated "options" list? I don´t need any hard-coded "options" at all. Just the dynamically generated one. And when I select from the list, I would like to get a response/reaction of any sorts.

What I have tried:

I am trying to capture the selected option via the following, but can´t get it to work.

if ($result->num_rows > 0) {
    $display = true;

    $select = []
    while ($row = $result->fetch_assoc()) {
        $select[] = "<option value=\"{$row['id']}\">{$row['fruit_name']}</option>";
    }
}