To reduce the attack surface of a system, administrators should perform which of the following processes to remove unnecessary software, services, and insecure configuration settings?

Harvesting is a term associated with data collection or credential gathering in offensive security contexts, not a defensive configuration process.

Windowing is not a recognized information security process for reducing attack surface.

Hardening is the well-defined security discipline of eliminating unnecessary features, services, accounts, and insecure default settings from a system to minimize its attack surface. It includes steps such as disabling unused ports, removing default credentials, uninstalling unneeded applications, and applying secure baseline configurations. This directly matches the described activity of reducing exposure through removal and reconfiguration.

Stealthing refers to making a system or activity less detectable, not to the removal of unnecessary software and services.