Which statement best describes the nature of public key encryption?

Public key encryption is best described by the statement that it relies on separate keys for encrypting and decrypting information. In this form of encryption, each participant has a pair of keys: a public key that is shared with others and can be used to encrypt messages, and a private key that is kept secret and used to decrypt messages that were encrypted with the corresponding public key. This separation of keys allows for secure communication without the need for both parties to share a single key, which is a fundamental benefit of public key encryption.

The other statements do not accurately capture the essence of public key encryption. The use of a single shared key pertains to symmetric encryption, which is a different method. Mentioning problems that are easier for humans than computers, or stating that algorithms cannot solve certain problems, doesn’t accurately align with the mechanisms and theoretical underpinnings of public key encryption, which typically relies on mathematical problems that are computationally difficult for modern computers to solve efficiently. This reliance allows for the secure exchange of information in an open environment.