Which media sanitization step protects confidentiality of data against a laboratory attack?

• A. Disposal
• B. Cleaning
• C. Purging
• D. Destroying

Answer: (C)

When thinking about protecting data confidentiality through media sanitization, you match the method to the level of threat you’re defending against. A laboratory attack implies a forensic-level attempt to recover residual data from the media after sanitization. Purging is the step designed to defeat that kind of recovery: it renders data unrecoverable by forensic tools and techniques that a lab might use. This often involves thorough overwriting, cryptographic erasure, or other procedures that leave no usable traces for a lab to extract.

Disposal focuses on getting rid of the hardware, but that doesn’t guarantee data can’t be recovered if the media is examined later. Cleaning is only removing surface dirt or basic contamination and does not address data remnants. Destroying physically damages the media to the point of data loss, but it’s a more destructive, less precise approach that isn’t aimed specifically at withstanding forensic recovery in a controlled setting.

So purging is the best fit for protecting confidentiality against a laboratory attack.