Three elements in a writers argument

Which of the following group roles has the responsibility of keeping the discussion on schedule?

What is a glossary? a statement of the author’s purpose in writing the book, which may include suggestions for using the book a page at the front of a book that lists units and chapters with their page numbers an alphabetical list of the specialized words and terms used in the book and their definitions an alphabetical list of all topics covered in the book and the pages on which they can be found

According to eric shlosser’s introduction to fast food nation what is his book primarily about?