<select id="mySelect">
<option value="1">Yes</option>
<option value="2">No</option>
</select>
<input type="button" id="demo" value = "Demo" />
<script type="text/javascript">
$("#demo").live("click", function () {
//Check whether option with value = 1 exists
var optionExists = ($("#mySelect option[value=1]").length > 0);
alert(optionExists);
});
</script>