A(n) __________ is an Extensible Scheme Standard file that is an approved W3C standard design as a basic infrastructure. A. HTML B. XML C. XSD D. XSL

The correct answer is C. XSD.

An XML Schema Definition (XSD) is an XML-based language for describing the structure of XML documents. It is an approved W3C standard design as a basic infrastructure.

HTML is a markup language that is used to create web pages. It is not an XML-based language.

XML is a markup language that is used to create structured documents. It is an approved W3C standard.

XSL is a language that is used to transform XML documents into other formats, such as HTML or XHTML. It is an approved W3C standard.