According to the BigFix Platform documentation, the Site Administrator is responsible for installing and maintaining the BigFix software, and to run administrative tasks that globally affect the environment such as site-level signing keys management. There is only one Site Administrator for a BigFix environment1.
Some of the global system options that the Site Administrator can set and modify are:
The default masthead file and license certificate
The default site subscription policy
The default client settings
The default relay settings
The default server settings
The default Web Reports settings
The default WebUI settings
The default LDAP settings
The default SAML settings
The default audit log settings
The default DSA settings
The default proxy settings
The default encryption settings
The default caching settings
The default logging settings
The default performance settings
The default security settings
The default diagnostic settings
To set and modify these global system options, the Site Administrator must use the BigFix Administration Tool, which is a separate application from the BigFix Console. The Site Administrator must also have the Action Site Credentials, which are a special key generated during the installation process.
The other options (A, B, and D) are not exclusive to the Site Administrator, and can be performed by other Console Operators, depending on their permissions and roles.
References:
BigFix Site Administrator and Console Operators
Site administrator responsibilities
Global system options
[BigFix Administration Tool]
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