characters who act and talk like real people, settings that are real and from modern times like homes, workplaces, bars and <span>restaurants, and the subject matter deals with real events and social/political</span>
The main purpose of expository text is to inform or describe what the story or book is about, so when the student reads they are understanding what is being read better. They can use this technique forever when reading and comprehening.
The answer is probably b or c.
The valley later became a center of mining for borax.
because Borax was the center valley.