* Applicable Requirement (CAP & Scoping): Assessors must use objective artifacts to validate system boundaries and scoping decisions. Network or topology diagrams are the most direct method to confirm logical and physical separation between environments handling CUI and those that do not.
* Why A is Correct: Network/topology diagrams provide a visual and technical representation of how isolation is achieved (e.g., VLANs, firewalls, segmentation). This is the primary evidence source for confirming separation.
* Why Other Options Are Insufficient:
* B: Change tickets/inventory show updates but not logical isolation.
* C: The SSP describes but does not demonstrate separation.
* D: Baseline configs show standard builds, not network isolation.
References (CCA Official Sources):
* CMMC Assessment Process (CAP) - Scope Validation
* CMMC Assessment Guide - Level 2 - Evidence Types (network diagrams, topology)

Testing may be performed on a mirrored system if the OSC can demonstrate that it is configured identically to the production system. The assessor must confirm equivalency through objective evidence before accepting test results.
Exact Extracts:
* NIST SP 800-171A: "Test assessment method involves exercising assessment objects under specified conditions... mirrored or replicated systems may be used if validated as equivalent."
* CMMC Assessment Guide: "If production systems cannot be tested, assessors may accept mirrored systems provided evidence demonstrates that the mirrored environment is representative of the production system." Why the other options are not correct:
* A/B: Testing must focus on systems and controls, not limited groups or customer matrices.
* C: Incorrect - mirrored systems are acceptable if validated as equivalent.
* D: Correct, as validation of equivalency is required.
References:
CMMC Assessment Guide - Level 2, Version 2.13: Testing methods and mirrored systems (pp. 6-8).
NIST SP 800-171A: Assessment methods (Examine, Interview, Test).

Comprehensive and Detailed in Depth Explanation:
The CMMC Assessment Process (CAP) requires evidence to be sufficient and complete across all in-scope systems handling CUI to validate compliance with practices like AC.L2-3.1.1 (Authorized Access Control).
While the evidence for the HR system (documents and interviews) is valid, it does not cover the Engineering Design Database and Manufacturing Control System, which are critical and in-scope per the network diagram.
CAP guidelines state that partial evidence covering only some systems is insufficient for a full assessment, as all CUI-related systems must be evaluated.
Option A (valid but incomplete) is close but not a CAP-defined category-evidence is either sufficient or insufficient. Option B (sufficient) overstates the evidence's scope. Option D (inconclusive) implies uncertainty, whereas the gap is clear. Option C (insufficient) aligns with CAP's requirement for comprehensive coverage, making it the correct answer.
Reference Extract:
* CMMC Assessment Process (CAP) v1.0, Section 4.2:"Evidence is insufficient if it does not address all in-scope systems and processes required by the CMMC practice."Resources:https://cyberab.org/Portals
/0/Documents/Process-Documents/CMMC-Assessment-Process-CAP-v1.0.pdf

Comprehensive and Detailed Explanation:
Boundary components in the CMMC Assessment Scope - Level 2 are network infrastructure elements (e.g., routers, gateways, virtualization systems) that define and protect the security boundary. The 3D printer, while a Specialized Asset if tied to CUI-related prototyping, is a peripheral device, not a core boundary component like Options A, C, and D. It doesn't inherently define or secure the network boundary, making B the correct answer.
Reference:
CMMC Assessment Scope - Level 2, Section 2.2 (Boundary Definition), p. 4: "Boundary components include network devices and systems, not ancillary equipment."

Comprehensive and Detailed in Depth Explanation:
By avoiding judgment and focusing on requirements, the CCA upholds Objectivity (Option C). Options A, B, and D are not directly relevant here.
Extract from Official Document (CoPC):
* Paragraph 2.2 - Objectivity (pg. 5):"Maintain objectivity by not providing opinions or recommendations during assessments." References:
CMMC Code of Professional Conduct, Paragraph 2.2.