Instructional materials are the content or information conveyed within a course. Like for example; textbooks, and reading books.
Answer:
the correct answer would be D. he tried different kinds of wood, coconut fiber, and even the hair because you see the word EVEN in between the AND and the THE, we'll the EVEN makes the sentence seem like the author is thinking that Edison really wants to succeed.
So D) is the correct answer.
Hope I helped.
Explanation:
The first paragraph talks abt the second one & more of the first to fully understand it
