How do encryption keys function in data security?

Encryption keys play a critical role in data security by ensuring the protection and confidentiality of information. Specifically, they are used to encrypt data, transforming it into a format that is unreadable without the correct key. This means that anyone who intercepts the encrypted data would not be able to understand it without access to the corresponding decryption key.

When data needs to be accessed by an authorized user, the encryption key is also used to decrypt the data, reverting it back to a readable format. This dual functionality of encrypting and decrypting data is fundamental to secure communication and data storage practices, protecting sensitive information from unauthorized access and breaches.

In contrast, user authentication, file compression, and network traffic monitoring involve different processes and functions that do not directly relate to the encryption and decryption processes that encryption keys facilitate. Thus, the option focused on the encryption and decryption capabilities accurately and comprehensively outlines the essential purpose of encryption keys in data security.