AppleWorks 6 requires that QuickTime 4 be installed. If the AppleWorks 6 Installer detects that QuickTime isn't installed in the active System folder, it will install QuickTime 4 for you.
If after installing the AppleWorks software, you disable the QuickTime software via the Extensions Manager and launch AppleWorks at a later date, AppleWorks will warn you that QuickTime needs to be enabled.
If you remove QuickTime from the active System Folder, the AppleWorks First Run installer will reinstall it for you.