Which element does a digital certificate directly provide to others?

• A. The subject's public key
• B. The private key
• C. The encryption algorithm
• D. The key exchange method

Answer: (A)

A digital certificate is a signed statement that binds an identity to a public key, issued by a trusted authority. The thing it provides to others is the subject’s public key. With that key, others can encrypt data intended for the subject or verify signatures created with the subject’s private key. The private key itself is never shared; it stays securely with the owner. While the certificate may indicate the algorithm used for the key (for example RSA or ECDSA) and other metadata, the actual element handed to others for use is the public key, not the private key, nor the encryption method or key-exchange technique itself.