An organization is experiencing multiple instances of attempted access from geographical locations where there are...

The correct answer is C — Adjust the firewall configuration to drop traffic from these addresses.

WGU Cybersecurity Architecture and Engineering (KFO1 / D488) teaches that the firewall is the primary network defense that can block or filter unwanted incoming traffic based on IP addresses, geographical locations, and other attributes. Dropping traffic from untrusted regions at the firewall level effectively prevents further access attempts.

Adjusting SIEM (A) can improve alerting but not blocking. DNS changes (B) relate to domain resolution, not access control. Proxy servers (D) can limit outbound traffic but are not primarily used for blocking geographic access inbound.

Reference Extract from Study Guide:

"Adjusting firewall rules to drop or block traffic based on IP addresses or geolocation is a primary defense against unauthorized access attempts from suspicious regions."

— WGU Cybersecurity Architecture and Engineering (KFO1 / D488), Network Security and Firewall Configuration

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