【select】
<!DOCTYPE html>
<html>
<head>
<script type='text/javascript'>
window.onload=function(){
selectElement.options[2].selected="selected";
}
</script>
</head>
<body>
<select id="selectElement">
<option>First</option>
<option selected>Second</option>
<option>3</option>
<option>4</option>
</select>
</body>
</html>
