What is the main purpose of a Certification Authority (CA) in secure communications?

The main purpose of a Certification Authority (CA) in secure communications is to create and assign certificates for encryption purposes. A CA is a trusted entity that issues digital certificates, which are used to verify the identity of individuals, organizations, or devices involved in electronic communications. These certificates authenticate the parties in an online transaction, enabling secure data transmission across networks by using encryption techniques.

The CA plays a critical role in establishing a trust framework in public key infrastructure (PKI) by ensuring that the public keys contained in the certificates are linked to the identified individuals or entities. This function prevents impersonation and ensures that the data exchanged remains confidential and intact.

While some of the other options mention aspects related to communication and transactions, they do not accurately capture the primary function of a CA. For instance, providing internet connectivity or monitoring financial transactions does not involve the cryptographic assurance and trust validation that a CA provides. Therefore, creating and assigning certificates is what distinctly identifies the function of a Certification Authority in the realm of secure communications.