Option B is the most appropriate. 'Domain Fronting' specifically manipulates the HTTP Host header. Therefore, 'xdr_http_sessions' is the ideal dataset as it provides parsed HTTP header information. The XQL query accurately filters for traffic to legitimate CDNs and then uses the 'alter' command with a 'case' statement to check if the 'Host:' header content differs from the actual 'dest_address' (the CDN domain). This logic directly identifies the core characteristic of domain fronting. Option A is too high-level (network sessions, not HTTP headers). Option C focuses on DNS, not the HTTP layer. Option D looks at a specific tool's command line, not all HTTP traffic. Option E relies on raw logs, which is inefficient and error-prone for structured data like HTTP headers.