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

Sentence1: Great. I was finally able to get you into the Autumn House staring Friday for 3 nights and 3 people. your booking reference is C5ARPTZ2 . Sentence2: Sorry about the confusion earlier. I was able to book your room at Leverton House for Friday, 3 nights for 3 people. The reference number is U5B3PHWC . Sentence3: It was my pleasure. Goodbye! Sentence4: Can you try 3 nights instead? Sentence5: Perfect. I would like to book it for 3 people for 4 nights starting on Friday. Sentence6: Awesome. Thank you for everything! Sentence7: I can help you with a taxi. Please tell me your departure and destination sites along with your time frame. Sentence8: Yes let's try a different hotel. Sentence9: How about Cambridge Contemporary Art, on 6 Trinity St? Entrance is free. Sentence10: The Leverton House is a guesthouse located on the east side of Cambridge. What information are looking for? Sentence11: Both of them are booked solid for the days you requested. Would you like a hotel in a moderate price? Sentence12: I'd like to visit a museum if possible. Sentence13: Can they accommodate 3 people for 4 nights? Also, what are their phone numbers? Sentence14: I'm sorry. I am unable to book your stay. Could you arrive on another day or stay for a shorter amount of time? Sentence15: I'm sorry, it doesn't look like the Leverton House will be able to accommodate you. How about Allenbell or Autumn House? They are in the same area and also inexpensive. Sentence16: Can you please check for 3 nights at the same hotel for 3 people and can I have the reference number? Sentence17: I'm sorry both of those hotels are booked solid. Would you consider slightly more expensive accommodations? Sentence18: Okay. I'll need a taxi too. Sentence19: I want to leave the hotel by 22:00 to go to the Museum you mentioned. Sentence20: I'm looking for places to go in the centre of town. Sentence21: I'm also going to need a taxi, please. Sentence22: Sure. But I still need to book a hotel. Is there anything else available? Sentence23: Do you have the phone number for Autumn House's front desk? Sentence24: There are many attractions in the centre of town. Could you be more specific about what you're looking for? Sentence25: I'm looking for information on the Leverton House hotel. Sentence26: Sure. It's 01223575122. Anything else? Sentence27: They don't have a room available for 3 nights either. Anything else you'd like me to try? Sentence28: A black skoda will pick up up at Leverton House at 22:00 and bring you to Cambridge Contemporary Art Museum. The contact number is 07697068185. Question: Who has spoken the sentence 15? (A) User (B) System
Answer: (B) System

Sentence1: Thank you for your help. Sentence2: do you have one with a star of 4? Sentence3: You're welcome, and have a great day. Sentence4: yes please tyhat you for all your help Sentence5: OK, you have 7 tickets reserved on TR6939. Total due at the station will be 116.2GBP. Your reference number is OK7WYTNQ . Sentence6: Try either one of the cheap ones, I need one that can hold my group of 7 for 5 nights on tuesday. Sentence7: Yes, I'll need 7 tickets. Sentence8: I also need a place to stay. 2 star is my preference. Sentence9: I would like to arrive in Cambridge by 08:45. Sentence10: We have 10 different trains on that day. Do you prefer a particular time? Sentence11: No, thank you. That will be all. Sentence12: TR6939 is your best option. It will leave at 05:39 and arrive at 07:07. Would you like to book passage on that train? Sentence13: In the west part of town. The price doesn't matter. Sentence14: the cambridge belfry was the best match for a large group so I booked you there, the reference number is X33MYBK5 , may I assist with anything else? Sentence15: Have a great time. Sentence16: I do. We have three options. Two that are cheap and one that's expensive. Do you have a preference? Sentence17: I need help finding a train. Can you do that? Sentence18: I don't have any 2 star hotels in that area. Would you like a different area or a higher rated hotel? Sentence19: Okay, do you need a reference number? Sentence20: Of course. Where are you traveling to? Sentence21: I would like to leave Liverpool street on Tuesday and arrive in Cambridge. Sentence22: okay, what area and price range? Question: Who has spoken the sentence 15? (A) User (B) System
Answer: (B) System

Sentence1: 51 Trumpington Street City Centre and cb21rg Sentence2: I need a place to dine in the expensive price range serving north indian food Sentence3: There are 29 hotels with those criteria. What location would you like it to be in? Sentence4: Unfortunately booking was unsuccessful is there another time you'd like to go? Sentence5: I am traveling to Cambridge and looking for a local restaurant. Sentence6: There aren't any restaurants serving expensive north indian food. Sentence7: I would like it to be in northern cambridge and have 2 stars. Sentence8: There are two hotels that meet those criteria, the Ashley Hotel and the Lovell Lodge. Sentence9: You're welcome. Have a good day. Goodbye. Sentence10: Yes, i was able to book the ashley hotel for two days. Your reference number is 6OMRC62I . Can I help with anything else? Sentence11: yes less than 100 a night Sentence12: Hi! I am looking for a place to stay that has free wifi. The hotel doesn't have to have free parking but that would be nice. Sentence13: There are many listings. Do you have an area or price range preference to further narrow down? Sentence14: Actually, I'm all set. Thanks again. Goodbye! Sentence15: Ok great, thank you! Sentence16: There are 6 restaurants listed, do you have a preference of area? Sentence17: Are there any that serve british food? Sentence18: Is there anything else you need help with? Sentence19: Can you try for 2 nights? Sentence20: Try Ashley Hotel for 6 people, 3 nights, starting Monday. Sentence21: I have 6 restaurants that serve expensive British food. Would you prefer one in the east, west or centre area? Sentence22: Centre would be fine. Could you give me the address and postcode, please? Question: Who has spoken the sentence 1? (A) User (B) System

Answer: (B) System