Option C closes both identified gaps. The URL exceptions currently let traffic avoid malware inspection, so they should be removed or narrowed. Zscaler added Newly Revived Domains to the Security URL super-category specifically for domains reactivated after a period of inactivity. A scoped URL Filtering block can stop web access to that category. Zscaler’s predefined DNS Control rule guidance also identifies newly revived domains among the threats that DNS Control can block, preventing resolution before a callback is established. Isolation still permits a controlled browsing session and is not the strongest response to suspected command-and-control callbacks. Raising a generic risk threshold is less precise, while detect-only IPS records activity without preventing it. Layered URL and DNS enforcement provides targeted protection with less disruption than a broad block.