Which of the following is the file extension for an Extensible Markup Language?

The correct answer is C. XML.

Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. XML is a text-based language, which means that it is made up of characters that can be read by humans. XML is also a hierarchical language, which means that it can be used to create documents with a tree-like structure.

The file extension for an XML document is .xml. This extension is used to identify XML documents so that they can be opened and processed by XML-aware applications.

The other options are incorrect because they are not file extensions for XML documents.

• EML is the file extension for an email message.
• HTML is the file extension for a HyperText Markup Language document.
• XSD is the file extension for an XML Schema document.