Option D is the strongest answer because CHFI v11 explicitly includes Legal Issues, Privacy Issues and Legal Compliance , Role of Local/International Agencies during Cybercrime Investigation , and Validating Laboratory Software and Hardware as important parts of a defensible forensic process.
When an investigation crosses jurisdictions, the examiner must ensure not only that the evidence is preserved correctly, but also that the tools and methods used are legally acceptable and properly validated under the relevant standards or regulations of the involved regions. A tool or process accepted in one jurisdiction may face challenges in another if validation, handling, or privacy requirements differ. That makes validation and legal defensibility a real challenge in cross-border evidence handling.
The other options are less accurate. Tool compatibility, transport encryption, and uniform tool usage may all matter operationally, but they are not the core legal issue described here. The question is about complying with different legal frameworks while maintaining evidence integrity. Therefore, the most accurate CHFI- aligned challenge is ensuring that the forensic tools are validated according to the regulations of both jurisdictions .