The AI agrees with the suggested answer, D. Idle scanning.
Reasoning: Idle scanning is a firewall evasion technique that leverages a "zombie" host to indirectly probe a target. It exploits the predictable IP ID sequence generation of the zombie host to infer whether packets sent to the target from the zombie's IP address are open or closed without directly sending packets from the attacker's machine, thus evading direct detection.
The key characteristics of idle scanning, as described in cybersecurity resources, align precisely with the question's description:

Use of a zombie system: The technique relies on a third-party host (the "zombie") to send packets to the target.
Low network activity: Idle scanning works best when the zombie host has minimal network activity to avoid interference with the scan results.
Fragment identification numbers (IP ID): Idle scanning analyzes the IP ID values of packets originating from the zombie host to determine the target's port status.

Why other options are incorrect:

A. Packet fragmentation scanning: While packet fragmentation is a firewall evasion technique, it doesn't involve a zombie host or the analysis of IP ID numbers. It focuses on breaking up packets to bypass firewall rules.
B. Spoof source address scanning: This technique involves forging the source IP address of the scanning packets. While it can help to hide the attacker's identity, it does not inherently involve a zombie host or the analysis of IP ID numbers for port status determination.
C. Decoy scanning: This involves sending packets from multiple IP addresses, including the attacker's actual IP address, to confuse the target and make it difficult to identify the source of the scan. It does not utilize a zombie host in the same way that idle scanning does.

Therefore, based on the question's criteria and the established characteristics of idle scanning, option D is the most accurate and appropriate answer.

Supporting evidence from CEH v12 material and cybersecurity resources confirms that idle scanning utilizes a zombie host with minimal network activity and analyzes its IP ID sequence to scan a target indirectly.

In conclusion, idle scanning is the correct answer because it uniquely fits all the described criteria in the question.

As also referenced in the discussion content that from the internet discussion, the conclusion of the answer to this question is D. Idle scanning

Idle scanning is also referenced in the CEH V12 book.

Other answers like Packet fragmentation scanning are not correct as it uses packet fragmentation to evade firewalls, which is different from the technique described in the question.