Under the CHFI v11 Operating System Forensics domain, investigators are required to analyze Windows file systems and recover evidence that may have been deleted, corrupted, or intentionally destroyed during a cybercrime. File loss incidents commonly occur due to malware infections, insider activity, ransomware attacks, or deliberate anti-forensic actions. Recovering such files is often critical to reconstructing events and identifying attacker intent.

R-Studio is a specialized forensic data recovery tool designed to analyze Windows file systems such as NTFS, FAT, and exFAT . It can scan allocated and unallocated disk space, identify lost partitions, and recover deleted or damaged files while preserving original metadata such as timestamps and file structure. CHFI v11 recognizes file recovery tools like R-Studio as essential for post-incident Windows forensics , especially when investigators must restore evidence without modifying the source media.

The other options are not appropriate for file recovery. Cain & Abel , Ophcrack , and Pwdump7 are credential-related tools used for password recovery or hash extraction and do not perform file system reconstruction or deleted file recovery. Using such tools would not help retrieve missing files and would not align with the forensic objective described.

Therefore, in accordance with CHFI v11 Operating System Forensics principles, the most suitable tool for restoring lost files from a compromised Windows system is R-Studio , making Option B the correct answer.