The correct answer is B because massive outbound HTTPS traffic is a strong indicator of data exfiltration, especially when it is designed to blend into normal web traffic. In CEH attack lifecycle concepts, exfiltration occurs after an attacker gains access and can quietly extract protected resources or sensitive data from the environment. The retrieved CEH-aligned material describes exfiltration as the phase where an attacker with elevated access can "quietly extract data," and notes that exfiltration can occur silently. HTTPS is commonly allowed outbound in enterprise networks, so attackers may use it as a covert or low-noise channel to move stolen files, credentials, database dumps, or archives to an external server. The guide material also notes that malware often uses SSL over port 443 or other easy- to-hide mechanisms rather than obvious suspicious ports. DoS usually creates service disruption, scanning generates probing patterns, and reconnaissance focuses on information gathering. Massive hidden outbound HTTPS most likely indicates data exfiltration.