Answer:
B. Symmetric key encryption
Explanation:
Symmetric key encryption is one in which a single encryption key is sent to the receiver so both sender and receiver share the same key. In this type of encryption, the sender uses a particular key to encrypt the data and sends the encrypted data (cipher data) to the receiver and then the receiver uses the same key to decrypt the data.
Public key encryption, or asymmetric encryption uses two keys - a private key and a public key. The public key is know to everyone while the private key is known only to those for whom the message is intended. An application of this type of encryption is in SSL (Secure Sockets Layer) - a protocol for transmitting data privately on the internet.
Private key encryption is not exactly one of the encryption methods but rather, a private key and a public key are used in encryption.
The best option is therefore <em>symmetric key encryption</em>.
<em>Hope this helps!</em>
