Advanced DNS Security is a cloud-delivered service that uses advanced analytics to identify malicious domains at the DNS layer. Option A describes DNS encryption (DNSSEC or DNS over HTTPS/TLS), which enhances privacy but doesn't inherently detect malicious domains. Option B correctly describes the core of Advanced DNS Security: using machine learning and threat intelligence (often correlated with WildFire, Threat Prevention, etc.) to analyze DNS queries and responses and identify malicious domains in near real-time. Option C is a function of a DNS server, not the security analysis provided. Option D is basic firewall filtering. Option E describes a basic, manual approach that doesn't scale and misses dynamic threats.