Representational State Transfer (REST) is the standard interface between

The correct answer is C. HTTP client and servers.

Representational State Transfer (REST) is an architectural style and set of rules governing the design of network-based applications. RESTful web services use HTTP methods (GET, POST, PUT, DELETE) to access and manipulate data.

A HTTP client is a software application that sends HTTP requests to a HTTP server. A HTTP server is a software application that receives HTTP requests from a HTTP client and returns HTTP responses.

The other options are incorrect because:

• Option A is incorrect because REST is not a standard interface between two machines in a LAN.
• Option B is incorrect because REST is not a standard interface between an HTTP client and a user.
• Option D is incorrect because REST is a standard interface between an HTTP client and servers.