A SYN scan sends TCP SYN packets to target ports and observes SYN/ACK responses without completing the TCP handshake, which results in many SYN packets without corresponding ACKs appearing in logs.

https://en.wikipedia.org/wiki/Web_application_firewall
A web application firewall (WAF) is a specific form of application firewall that filters, monitors, and blocks HTTP traffic to and from a web service. By inspecting HTTP traffic, it can prevent attacks exploiting a web application's known vulnerabilities, such as SQL injection, cross-site scripting (XSS), file inclusion, and improper system configuration.

The correct answer is A. Stolen equipment. In CEH ethical hacking methodology, "stolen equipment" is a mode of ethical hacking that simulates theft of a critical information resource, such as a laptop owned by an important organizational user, and then provides that asset to the ethical hacker for assessment. The question specifically mentions targeting the CEO's laptop or backup tapes to extract critical information, usernames, and passwords. These are classic examples of sensitive assets that may contain cached credentials, confidential documents, password hashes, VPN profiles, email archives, or backup copies of production data.
This test evaluates whether protections such as full-disk encryption, strong authentication, secure backup handling, and data-at-rest controls are effective. "Physical entry" focuses on entering and compromising the organization's facilities or ICT infrastructure, while "insider attack" simulates a trusted internal user abusing access. "Outsider attack" typically represents an external threat. Because the focus is on stolen laptops and backup media, the best CEH answer is stolen equipment.

The correct answer is D. Hoax Letters that Spread False Security Warnings.
The message is designed to create fear and urgency through false or unverifiable claims about a malware outbreak. It does not contain a malicious attachment, does not ask for credentials, and does not directly request payment. Its purpose is to spread a false warning and cause disruption or unnecessary concern.
CEH-aligned social engineering material lists Hoax letters, Chain letters, and Spam as forms of computer- based social engineering delivered through email and messaging channels .
Option A. Scareware is incorrect because scareware usually tricks users into installing rogue software or paying for fake protection.
Option B. Spam Email is too broad; spam refers to unsolicited bulk email, while the content here is specifically a false warning.
Option C. Chain Letters is close because the message encourages forwarding, but the stronger classification is hoax letter because it spreads a false security warning.
Option D. Hoax Letters is correct because the message relies on fabricated security claims to trigger fear and forwarding behavior.
Therefore, the best answer is D. Hoax Letters that Spread False Security Warnings.