Choosing a good reviewer for your writing means finding someone who A. concentrates on correcting your spelling and grammar errors. B. is a close friend and will give you a positive review. C. will concentrate on your ideas and how well you support them. D. knows everything about writing and will find every mistake.
I'd say C. will concentrate on your ideas and how well you support them. It wouldn't be B. because it'd be a biased review, and It wouldn't be D. because no one knows everything about writing + would find every mistake.