According to Guide to the Secure Configuration of Red Hat Enterprise Linux 6, there is this policy:
"In certain scenarios, it is beneficial to remove certain httpd modules to limit the functionality of the HTTP Server. To do so, simply comment out the entire line which loads the module you wish to remove in the /etc/httpd/conf/httpd.conf file".*
How should I know which modules are needed for some web application? Particularly I want to deploy MediaWiki. I searched its wiki, and didn't find such topic in its security page.