JSFiddle - React, Tailwind, and code Playground
HTML
<html>
<body>
<select id='a_drop_down_box'>
<option value='1'>One</option>
<option value='2' selected='selected'>Two</option>
<option value='3'>Three</option>
</select>
<p id='message'></p>
</body>
</html>
JavaScript
var test = document.getElementById("a_drop_down_box");
var value= test.options[test.selectedIndex].value;
alert(value);
var test = document.getElementById("a_drop_down_box");
var value= test.options[test.selectedIndex].text;
alert(value);