Which of the following describes the function of symmetric encryption?

Symmetric encryption is characterized by the use of a single secret key for both the encryption and decryption processes. This means that the same key that is used to encrypt the data must also be used to decrypt it, ensuring that both the sender and receiver have access to this key. The primary advantage of symmetric encryption is its speed and efficiency, making it suitable for encrypting large amounts of data quickly.

In symmetric encryption, if the key is kept secure and is not shared with unauthorized individuals, the confidentiality of the encrypted data is maintained. This method is commonly utilized in various applications where secure and efficient data transmission is required, such as in file encryption and secure communications.

The other options refer to different encryption concepts. The use of multiple keys pertains more to asymmetric encryption, where a pair of keys (public and private) is utilized. The automatic generation of new keys refers to a practice not typically associated with symmetric encryption, and verification via a public key infrastructure aligns with asymmetric encryption methodologies, which leverage different keys for encryption and decryption, enhancing security during the transmission of sensitive data.