Given the task definition and input, reply with output. You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.

Sentence1: I do recommend huntingdon marriott hotel, but it is in the expensive price range. I want to confirm this is okay before booking. Sentence2: Thank you, have a great day, goodbye! Sentence3: Either is fine. Can you book a room for 7 people for 2 nights? We'll arrive on Friday. Sentence4: Your booking for a party of 7 arriving on friday for 3 days 2 nights was successful. Your Reference number is DZ1T0E9N . Is there anything else I can assist you with? Sentence5: No, that is all. Thanks for the help. Bye. Sentence6: There are two options available, which would you prefer cheap or expensive? Sentence7: I am looking for a 4 star hotel with free wifi in the west side of town. Sentence8: That sounds great. Thanks. Question: Who has spoken the sentence 4? (A) User (B) System
Answer: (A) User