You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.

Sentence1: Unfortunately, I am not seeing any 4 star hotels that are moderately priced in the centre. We could try a cheaper hotel or a guesthouse? Sentence2: Sure do. Their address is fulbourn, postcode cb15dh. Phone number is 01223295264, and entrance is free. It's a museum on the Eastside. Sentence3: Nevermind. Do you have info on gallery at twelve a high street. Sentence4: Thank you very much for your help, have a nice day. Sentence5: Thank you, enjoy your stay in cambridge. Sentence6: Of course. We have so many attractions! What part of town will you be in? Sentence7: I will be visiting Cambridge soon and can't wait to see some of your local attractions. I do need your help with some information. Sentence8: I'm sorry, but there are no cheap hotels in the center of town, either. The only cheap hotel is on the west side. Sentence9: How about in the cheap price range? Sentence10: I have two options. Would you prefer a hotel or a guesthouse? Sentence11: I need a 4 star room in the centre please. Sentence12: A hotel in the moderate price range. Thank you! Question: Who has spoken the sentence 4? (A) User (B) System
Answer: (A) User

Sentence1: Yes, and their phone number is 01223363682. Is there anything else I can help you with? Sentence2: Do they have free parking, and what is their phone number? Sentence3: Yes I can confirm that Warkworth house has internet, can I help with anything else? Sentence4: Can you tell me if warkworth house hotel has wifi. Sentence5: Sure. Glad to help. Sentence6: No, that's all I need, thank you. Question: Who has spoken the sentence 5? (A) User (B) System
Answer: (B) System

Sentence1: That sounds good can you book it for 4 people at 16:30 on wednesday? Sentence2: Yes. The Bedouin serves gastropub food and is in the centre of town. Sentence3: The Slug and Lettuce would be fine. It will need to be on Wednesday for 4 people. We'd like to eat at 16:30. Sentence4: Yes, I would prefer to stay in the south. Sentence5: Okay, I've got it booked for you for 4 people for 3 nights starting on Wednesday. The reference number is: HRT9EL5L . Is there anything else I do for you? Sentence6: That is all I need to know. Thanks. Sentence7: You're all set. Your car will be a white toyota. If you need to contact the driver, you can call 07073603005. Sentence8: You are welcome, just let me know if you need anything else. Sentence9: Yes what time would you like to travel by taxi? Sentence10: i am also looking for a place to stay. The hotel should be in the cheap price range and should include free wifi. Sentence11: Okay, you're all booked. Your table will be reserved for 15 minutes and your reference number is 32V8AA4N . Is there anything else I can help you with today? Sentence12: Is that a gastropub? Sentence13: I apologize the Bedouin serves african food. Could I recommend the Slug and Lettuce, or backstreet bistro, if you would prefer something moderately priced the cow pizza kitchen and bar. Sentence14: Cambridge has 10 options that meet your criteria. Is there a particular area in which you would like to stay? Sentence15: I'm looking for somewhere to eat in the centre. Sentence16: I would like to arrive in time for our booked time at the Slug and Lettuce. Sentence17: The bedouin is a nice choice. Do you want to book ? Sentence18: Rosa's bed and breakfast is a guesthouse in the south, with a 4 star rating, free wifi and cheap price range. Would you like a reservation? Sentence19: Yes, please book a stay for 4 people, 3 nights, starting on Wednesday. Sentence20: Can you also book a taxi for me between the guesthouse and the restaurant? Question: Who has spoken the sentence 18? (A) User (B) System
Answer: (A) User