The sentence finishes with a string of "wh-" noun clauses. These clauses are usually not thoughts, so the last one should also not be a question. "Which a single will be the best" is clearly a question format, so it is sensible that " This could not use "It's" that's https://zed-directory.com/listings13318592/indicators-on-female-psychiatrist-in-islamabad-you-should-know