The sentence finishes having a string of "wh-" noun clauses. These clauses are usually not concerns, so the final 1 must also not be a matter. "Which 1 is definitely the best" is obviously a question structure, so it is smart that " Hello, Thanks for your review. Thank you https://share.evernote.com/note/8017dd9b-bae1-b7b2-e7a5-981f51e2ee16