I have a select statement like this:

<select onchange=change_session() name=select_path id=select_path>

    <option name=sserver_id id=select_path selected value={{ i.id }}>{{ default_server_id }}</option>

    {% for i in all_server_id %}

        <option name=server_id id=select_path value={{ i.id }}>{{ i.session_name }}</option>                 

    {% endfor %}

    </select>

The first option show the default_id on the top and the second options lists all the options. User can change the option and process accordingly which is send to server using AJAX. Now I want to find out which server_id has user selected using JavaScript like this:

var serverId=document.getElementById('server_id');

How can I get the selected option?