Answer:
The correct proxy server role that stores frequently accessed data so that a user's request never has to leave the network for retrieval is a caching proxy server. It stores a copy of previously retrieved pages and files locally, allowing faster access to web pages and reducing bandwidth usage. When a user requests a previously accessed file or web page, the proxy server can provide it from the local cache, rather than fetching it again from the internet, which results in faster response times and reduces network congestion.