Synonym of COMPENDIUM

Answer: Option D

Glossary : an alphabetical list of words relating to a specific subject, text, or dialect, with explanations; a brief dictionary.
Reference : the action of mentioning or alluding to something.
Index : (in a book or set of books) an alphabetical list of names, subjects, etc. with reference to the pages on which they are mentioned.
Summary : a brief statement or account of the main points of something.
Compendium : a collection of concise but detailed information about a particular subject, especially in a book or other publication.

Synonym of Compendium is Summary