Whih two factors combine to form an authors purpose

Which two factors combine to form an author's purpose for writing a text? audience and message imagery and repetition narrator and narrator's point of view tone and word choice but it's asking to put them together.

Explanation:

the statement that best explains why the tenth amendment reserves some rights and powers to states is that the framers believed in the principle of federalism. this principle says that some powers are in the hands of a centralized national government, while others are reserved for the governments of several states.

i am also pretty sure it is c