What role does a Certification Authority (CA) serve in secure communications?

A Certification Authority (CA) is fundamental in secure communications because it issues digital certificates and manages encryption keys, which are essential for ensuring the integrity and authenticity of communications over the internet. The CA validates the identity of entities requesting certificates, which allows these entities to establish secure connections and encrypt data.

When a user or organization wants to communicate securely, they can use a digital certificate issued by a CA to establish trust. This digital certificate includes the public key of the entity, which is necessary for secure data transmission and typically includes information about the key, the identity of the holder, and its expiration date. The CA's role involves verifying the identities of the entities before issuing certificates, and it also maintains the revocation lists to help entities check the validity of certificates.

This trust framework is critical in various applications, such as e-commerce and online banking, where sensitive information, like financial data, is transmitted. Since the other options do not encompass the CA’s role of managing certificates and encryption keys, they do not accurately identify its function in the realm of secure communications. Thus, the correct answer effectively highlights the responsibility of the CA in the broader context of cybersecurity.