What is the key distinction between public and private keys?

The key distinction between public and private keys lies in their roles in the encryption and decryption processes within asymmetric cryptography. Public keys are primarily utilized for encryption, allowing anyone to encrypt a message intended for the owner of the corresponding private key. This is pivotal in ensuring that only the intended recipient can decrypt and read the message using their private key.

Private keys, on the other hand, are kept confidential and are used exclusively for decryption. This arrangement ensures that while anyone can encrypt a message using the public key, only the holder of the private key, who should keep it secure, can decrypt that message. This asymmetric approach is foundational to secure communications, providing a mechanism for confidentiality and secure data exchange over potentially insecure channels.

The other options misrepresent the roles and characteristics of public and private keys, leading to misunderstandings about how asymmetric encryption works. For instance, public keys are not kept secret nor shared openly, as indicated in option A, and they serve a clear purpose in the encryption process, not as a mere theoretical concept as suggested in option C. Similarly, the notion that public keys are encrypted while private keys remain unencrypted in option D does not accurately reflect their respective functions, as public keys are indeed meant to be shared openly and used