During the confession, which technique was used to hide pictures within other pictures?

• A. Typography
• B. Steganalysis
• C. Picture encoding
• D. Steganography

Answer: (D)

Steganography is the practice of hiding data inside another medium so that the hidden content remains unseen. Hiding a picture inside another picture is a classic example: the embedded image blends into the host image, often by tweaking the pixels in a way that isn’t noticeable to the eye. In digital forensics, this technique is used to conceal information within images, audio, or other files, making it hard to detect without special tools.

Steganalysis is the process of detecting whether such hidden data exists and possibly extracting it; it’s the investigative counterpart, not the method of concealment itself. Typography and picture encoding don’t describe the concealment of one image inside another, so they don’t fit this scenario.