Answer:
Inform - the author wants to tell or teach you something.
Explanation:
Instructional booklets are written for the purpose of telling teaching users (of products/items) how to use that product. They increase user's knowledge and information of that product. So the purpose of Instructional booklets is to inform the readers.
Persuasive writings try to persuade reader into believing the ideas of the author to be correct, e.g. An author persuades government authorities to enhance efforts to reduce Carbon dioxide emission into air.
Entertainment writings' main purpose is to entertain the reader, such as novels, poetry, songs, thrillers etc. But apart from entertaining they may also inform and/or persuade the readers as well.
