What is described by WSDL in the context of web services?

WSDL, which stands for Web Services Description Language, is an XML-based language that is primarily used to describe the functionalities offered by a web service. It provides a machine-readable description of the services available, including the methods that can be invoked and the parameters required for those methods. This allows clients to understand what operations they can perform on the web service and how to interact with it.

While WSDL may include information about data types and how messages are structured, its primary role is to define the behavior of the web service itself, detailing the services it provides and how these services can be accessed. This makes option C the clear choice, as it captures the essence of what WSDL is fundamentally intended to convey regarding the web service’s functionality.