Extracty query from included js script

script query extract.md

<script src="js/somefile.js?option=1,option2,option3"></script>

query = document.getElementsByTagName("script");
query = query[query.length - 1].src;
if (- 1 == query.indexOf("?")) query += "?";
query = query.substr(query.indexOf("?") + 1);
console.log(query);