Answer

(i) with external access

Explanation

A proxy server acts as an intermediary between a client and another server, commonly on an external network such as the Internet. Instead of directly contacting the destination server, the client sends its request to the proxy, and the proxy forwards the request and returns the response.

A proxy can provide functions such as:

• Controlled external access to Internet resources.
• Caching frequently requested content.
• Filtering and access control according to organizational policies.
• Privacy/security by hiding internal client details from external servers in some configurations.

Option analysis

• (i) with external access: Correct in the context of this MCQ. A proxy mediates access between an internal client and external resources.
• (ii) acting as a backup: Backup servers are used for redundancy/data recovery, not as the primary definition of a proxy.
• (iii) performing file handling: File handling is not the defining purpose of a proxy server.
• (iv) accessing user permissions: A proxy may enforce access policies, but user-permission management is not its fundamental role.

Final answer: (i) with external access.