A.It provides additional information that narrows the focus
of the text.
Explanation:
By dividing the Guide into different sections and giving them specific titles, the author is separating information in an organized and effective way. This is the purpose of narrowing the focus of a text. In this way, the text satisfies the reader's neccesities, meaning that any person who reads the guide will have access to precise information he/she may be looking for, without the need of going over other unnecessary information.
