Answer:
b. Asymmetric encryption.
Step-by-step explanation:
Asymmetric encryption, also known as public-key cryptography, is a type of encryption that uses two different keys - a public key and a private key. The public key is used to encrypt data, while the private key is used to decrypt it. This type of encryption allows for secure communication over insecure channels, as only the intended recipient with the matching private key can decrypt and read the message.