Answer :
Final answer:
The website foo.com sends a certificate to Alice containing foo.com's public key, which is signed with the Certificate Authority's private key, serving to validate and authenticate foo.com's identity and enable secure communications. So, the correct option is A. The certificate includes foo.com’s private key, signed by the CA’s public key.
Explanation:
When Alice initiates communication with the website foo.com, and she receives the site's certificate, the correct statement about this certificate is: The certificate includes foo.com's public key, signed by the Certificate Authority's (CA's) private key. Public key certificates are essential for establishing a secure connection and authenticating the communicating parties. In the asymmetric encryption system, a public key is used to encrypt data, which can only be decrypted by the corresponding private key. Thus, the certificate entails foo.com's public key, which is utilized by clients, like Alice, to encrypt messages or verify signatures. The certificate is signed by the CA's private key to validate the identity of the holder of the corresponding public key and to prevent various cyber-attacks, such as Man in the Middle Attacks (MIMA).
