im new to codeginiter and its developing. i used dropbox (html select box) when i pressed option there. i need to trigger a alert box.in oder to do that i used following code. But it didnt work on me. and i could find the mistake i've done please help me. 

```
<html lang="en">
    <head>
        <meta content="text/html;charset=utf-8" http-equiv="Content-Type">
        <meta content="utf-8" http-equiv="encoding">

        <title>Ask Questions</title>
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <meta name="description" content="">
        <meta name="author" content="">

        <link href="<?php echo base_url(); ?>css/bootstrap.min.css" rel="stylesheet">
        <link href="<?php echo base_url(); ?>css/style.css" rel="stylesheet"> 

<script type="text/javascript" src="<?php echo base_url(); ?>js/jquery.min.js">

                   // untill select catogory tags are disabled

                   function activate_match()
                   {
                      // var tnmt_id = "hip hure";
                       alert("tested");
                       //Get the id of the tournament selected in the list
                   }

</script>

    </head>

<body>
        <div class="container">
            <p class="help-block">
                How to Ask </br>
                Is your question about DIY ? </br>
                We prefer questions that can be answered, not just discussed.<br>
                Provide details. Share your experience. </br>

            </p>

            <div class="form-group">

                <?php
                echo form_open('homepage/askquestionview');
                echo validation_errors();
                ?>  
            </div>

            <p> </p>

            <div class="form-group">

                <select name="cat" id="cat" onchange="activate_match()">
<?php
                   foreach($catogories as $cat) {
                    echo'<option value="' . $cat . '">' . $cat . '</option>';
                }
                ?>

                </select>

            </div>

            <div class="form-group">
                <p>
                    Description: <br/>

                    <textarea name="decription" rows="5" cols="100"> </textarea>
                </p>
            </div>

            <p></p>                

            <div class="form-group">
                Declare new Tags:<br/>

                <input type="text" value="" name="tag">
                </p>
            </div>

        </div>                             <p>
            <input type="submit"  class="btn btn-success btn-block" value="Post Your Question" id="postQuestion">
        </p>
        <?php echo form_close(); ?>

    </body>

</html>

```