Are you looking to get a selected option text using javascript ? You can easily find the selected value using javascript. but if you need to find the option text (selected text) using javascript, i am here to give you solutions. Have a look at below code to get selected dropdown text using javascript.
<script type="text/javascript">
function option_text(){
elm = document.getElementById('category');
alert(elm.options[elm.selectedIndex].text);
}
</script>