After a remote command execution incident occurred on a web server, a security analyst found the following piece of code in an XML file:

Which of the following is the BEST solution to mitigate this type of attack?

A. Implement a better level of user input filters and content sanitization.
B. Properly configure XML handlers so they do not process &ent parameters coming from user inputs.
C. Use parameterized queries to avoid user inputs from being processed by the server.
D. Escape user inputs using character encoding conjoined with whitelisting.