Repopulating select after ajax request

[Madrid]

I have a select which allows the user to select multiple option. Also on the same page is a form that will allow the user to add new keywords which will appear in the select.My javascript sends an ajax request to a php script which either returns a success or error message which then gets added to the dom.The ajax part of the script looks like this\[code\]$.post( metadataAction, { dateOfUpdate:dateOfUpdateVal, metadataStandardName:metadataStandardNameVal, metadataLanguage:metadataLanguageVal }, function(responseText) { $('body').append(responseText); }, "html");\[/code\]I only want to repopulate the options when a new keyword has been successfully added.Does anyone have any suggestions on the best way to achieve this?Thanks for any help.