You are given a sentence from a conversation between a human and a virtual assistant. Your task is to identify whether the sentence is a question or not. Answer with Yes or No.

Example Input: Yes. What's their phone number?
Example Output: Yes

Example Input: Yes, that sounds right. What's their number, and do they serve alcohol?
Example Output: Yes

Example Input: I want to watch the movie with subtitles.
Example Output:
No