I think it's explanation since the text shows comparison which isn't direct, ni similar words are present, ruling out synonyms and examples aren't present in the text.
The inclusion of reputable sources and specific facts would best strengthen the author's main argument because it would offer factual proof instead of just the author's opinion on the matter.
A would be the sentence with a confusing antecedent, because the "he" could have been referring to "Uncle Arthur" or "Benjamin."
