To answer this question, you need to understand the concept of XML (eXtensible Markup Language).
Option A) eXtra Markup Language - This option is incorrect because XML does not stand for "eXtra" Markup Language. XML is not specifically designed to provide extra markup, but rather to provide a flexible and extensible way to structure and store data.
Option B) eXplore Markup Language - This option is incorrect because XML does not stand for "eXplore" Markup Language. XML is not primarily used for exploring or browsing purposes, but rather for storing and exchanging data.
Option C) eXpensive Markup Language - This option is incorrect because XML does not stand for "eXpensive" Markup Language. The cost of using XML is not related to its name; it is a widely-used and freely available markup language.
Option D) eXtensible Markup Language - This option is correct because XML stands for "eXtensible" Markup Language. XML is designed to be easily readable by humans and machines, and it allows users to define their own markup elements and tags.
The correct answer is D) eXtensible Markup Language.