The correct answer is B - Internet Protocol Security (IPsec).
According to WGU Cybersecurity Architecture and Engineering (KFO1 / D488), IPsec provides secure communication over IP networks by encrypting and authenticating IP packets. It is widely used for site-to-site VPNs and ensures confidentiality, integrity, and authentication between different cloud environments like Azure and AWS.
TCP (A) is a transport layer protocol ensuring reliable delivery but not encryption. FTP (C) is used for file transfer and is insecure unless secured with extensions. SSH (D) secures remote terminal sessions but is not primarily used for network-wide secure communication.
Reference Extract from Study Guide:
"IPsec provides a secure method of communication across IP networks, ensuring data confidentiality, integrity, and authentication for VPN connections and hybrid cloud communications."
- WGU Cybersecurity Architecture and Engineering (KFO1 / D488), Secure Protocols for Hybrid Environments