Secure Sockets Layer/Transport Layer Security (SSL/TLS) is the correct answer because it is a protocol that provides end-to-end security of data sent between applications over the internet. It ensures the confidentiality and integrity of the data in transit through encryption and can be recognized by the 'https://' at the beginning of a web address. A web application firewall (WAF) is primarily used to filter, monitor, and block HTTP traffic to and from a web service but does not encrypt data in transit. Network segmentation divides a computer network into subnetworks to improve performance and security, but does not provide encryption. Role-based access control (RBAC) is a method of regulating access to computer or network resources based on the roles of individual users within an organization, and is not concerned with data in transit. Intrusion prevention systems (IPS) are network security appliances that monitor network and/or system activities for malicious activity. While an IPS may prevent some forms of eavesdropping by blocking attacks, it does not provide encryption.