Identify the Letter of the Choice That Best Matches the Phrase

Identify the letter of the choice that best matches the phrase or definition.
-Program that checks the document for errors in syntax and content

A) SGML
B) system-independent
C) XML
D) DTD
E) well-formed
F) namespace
G) XHTML
H) CDATA
I) character set
J) W3C
K) parser
L) valid