Steganography is the correct answer because it is a security technique used to hide information within another file, message, image, or video. It is a form of obfuscation that protects the confidentiality of data by making it undetectable to unintended recipients or observers. Unlike encryption, steganography does not make the data unreadable, but rather hides the fact that there is any data to be protected at all. Tokenization and data masking, on the other hand, are used to protect data by replacing sensitive elements with non-sensitive equivalents and are not about hiding data within other data.