An attacker gained access to the hosts file on an endpoint and modified it.

When the hosts file is altered, local name resolution is compromised, and domain queries are redirected to malicious IP addresses. This is a form of DNS spoofing/poisoning, where false mappings trick users into visiting fraudulent websites.

B. Phishing typically uses emails or messages to trick users, not local file modification.

C. VLAN hopping is a Layer 2 attack to gain unauthorized network access, unrelated to DNS.

D. ARP poisoning manipulates ARP tables on a LAN to reroute traffic, not name resolution.

References (CompTIA Network+ N10-009):

Domain: Network Security — DNS poisoning/spoofing, host file manipulation, endpoint attacks.