Which of the following is NOT an example of a RESTlet?

A RESTlet is a scriptable RESTful web service that allows for the interaction with NetSuite's data and functionality through web requests. It typically operates by handling requests sent in different formats, including JSON and XML, and can perform various operations such as creating, reading, updating, or deleting data.

In this context, the correct answer highlights that XML is a data format used by RESTlets for transmitting structured information, not an example of a RESTlet itself. RESTlets are built to interpret and respond to data requests made in various formats, whereas XML simply serves as one of those formats. Authentication is a necessary component for securing RESTful services but does not define the structure or operation of a RESTlet, nor does REST itself refer to a specific implementing script; it describes the architectural style.

JSON, similar to XML, is also a format that can be utilized with RESTlets, reinforcing that while formats are integral to how RESTlets function, they do not represent the RESTlet concept. This nuance makes it clear why XML, although related, is not considered an example of a RESTlet.