How should the developer prevent a cross site scripting vulnerability?

A developer has a Apex controller for a Visualforce page that takes an ID as a URL parameter.

How should the developer prevent a cross site scripting vulnerability?
A . ApexPages.currentPage() .getParameters() .get(‘url_param’)
B . ApexPages.currentPage() .getParameters() .get(‘url_param’) .escapeHtml4()
C . String.ValueOf(ApexPages.currentPage() .getParameters() .get(‘url_param’))
D . String.escapeSingleQuotes(ApexPages.currentPage() .getParameters(). get(‘url_param’))

View Answer

Answer: D