If unauthorized or non-standard applications are appearing on systems and users are receiving licensing prompts, it's likely users are installing software themselves. Removing users from the local administrators group will prevent them from installing software without approval and reduce the likelihood of introducing unapproved or malicious programs.

A . Deploying a PKI helps with secure communications but doesn't address user software installation rights.

C . Blocking suspicious websites is helpful but doesn't prevent local installations.

D . Stricter UAC may add prompts but can still be bypassed by admin users.

CompTIA A+ 220-1102 Objective 2.2: Compare and contrast access control methods and user privilege settings.

Study Guide Section: Principle of least privilege and managing local admin rights

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