CompTIA Security+ (SY0-501) — Question 762

An email recipient is unable to open a message encrypted through PKI that was sent from another organization. Which of the following does the recipient need to decrypt the message?

Answer options

• A. The sender's private key
• B. The recipient's private key
• C. The recipient's public key
• D. The CA's root certificate
• E. The sender's public key
• F. An updated CRL

Correct answer: E

Explanation

To decrypt a message encrypted with PKI, the recipient needs the sender's public key to verify and unlock the message. The sender's private key is not accessible to the recipient, and the recipient's own keys are not useful for this purpose. The CA's root certificate and an updated CRL are also unrelated to the decryption process.