Edwards' primary means of persuasion is

Edwards uses explicit pathos to strengthen his argument, and ethos to remind the audience of gods absolute power. Tone is the technique by which the author conveys his attitude toward the subject.

Explanation:

a biography is a genre that mainly accounts somebody's life and that is written by somebody else. this genre supports sonia nazario's desire to share enrique's life because she can fully inform readers of his entire emotional journey.

in a biography, an author can share the readers almost everything about a person's life, or just one key event or personal aspect the author is interested in telling, like in this specific case in which sonia nazario is centered in enrique's emotional journey.