Answer:
A
Step-by-step explanation:
Where might you gain insights to what is important within content you are about to read?
Chapter Questions will actually give an oversight into themes and issues raised in the chapter. They are very useful to point to the reader the summary of ideas raised within the chapter.
Glossary are used to document terms and meanings used within in a book
index gives page numbers of words
Table of contents: Puts chapters into section and subsection. It makes the reader have an overview of the content of document.
So A is correct