[Mukhtar]

$(document).ready(function(e) {
       $('#mySelect').change(function(){
            var id = $(this).data("section");
            $('#'+id).show();     
        });
            e.preventDefault(); 
    });

<select name="mySelect" id="mySelect">
<option value="0" data-section="item1">item1</option>
<option value="1" data-section="item2">item2</option>
</select>
<div id="item1" style="display:none;">
text1
</div>
<div id="item2" style="display:none;">
text2
</div>