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

Sentence1: Ok great! I was able to get you booked, your reference number is N4TJE8VR . Is there anything else that I can help you with? Sentence2: Yes please. There are 5 of us total and we need 4 nights in a row. Thank you. Sentence3: May I get your departure and destination information please? Sentence4: Can you verify the cost for train TR6954 for me? Sentence5: There don't seem to be any 5-star lodgings in the city. Would you like to try searching for 4 stars instead? Sentence6: I am looking for a train arriving by 9:45 on Tuesday. Sentence7: I'd like to start my stay on Tuesday, please. Sentence8: Your booking reference is NT43PSC0 . Now, if you let me know what type of hotel you are interested in, I can help you with that as well. Sentence9: TR6954 departs from Leicester at 07:09 and arrives in Cambridge at 08:54. Would you like to book this train? Sentence10: What day would like to start your stay? Sentence11: Maybe... how much does it cost? Sentence12: Yes, 4 stars would be fine. Sentence13: Nope, that'll take care of everything, thanks! Sentence14: I am going from Cambridge to Leicester. Sentence15: I'm sorry, we have that mixed up. I need to depart from leicester and go to cambridge. Do you have a train that arrives by 09:45 in cambridge? Sentence16: The acorn guest house is a 4 star hotel located in the north side. Would you like to make reservations? Sentence17: You're welcome. Have a great stay! Sentence18: TR2863 departs from Cambridge at 07:21 and arrive in Leicester by 09:06. Would you like to book this train? Sentence19: Yes I would like help with booking the train and I will also need to book a hotel. Sentence20: It costs 37.80 pounds per ticket. Sentence21: The cost for this particular train is 37.80 pounds per ticket. Would you like assistance booking tickets for this train? Sentence22: Can you help me find a 5-star room somewhere that offers free parking and wifi? Question: Who has spoken the sentence 17? (A) User (B) System
Answer: (B) System

Sentence1: Yes, after 8:30 would be best. Sentence2: I have booked you a train ride on TR6488 which will depart at 09:21 and will arrive at 10:10. The total fee will be 10:24GBP. Would you like the reference number? Sentence3: No thank you. Thanks for your help. Sentence4: Great, thank you. That's all I needed. Sentence5: What is the total travel time? Sentence6: The post code is cb21ab and the phone number is 01223323737. Where would you like to book a train to? Sentence7: Where are you departing from? Sentence8: I would like the post code and phone number for the restaurant please, and I would like to book a train. Sentence9: The total travel time will be 49 minutes. Sentence10: You're welcome. Is there anything else I can do for you today? Sentence11: I'm leaving from Cambridge. Sentence12: I think something cheap. If not, go up to moderate. Sentence13: Do you have a time in mind? Sentence14: Good day to you. Sentence15: I suggest pizza hut city centre, it has a cheap price range. Would you like me to book it or would you like more information? Sentence16: Yes, Please book the reservation. Sentence17: I need to go to Stevenage on Sunday. Sentence18: I'd be happy to book a table for you. Please let me know the day, time, and the number of people in your party. Sentence19: There are nine of them. What price range do you prefer? Sentence20: I am looking for an Italian restaurant located in the centre of Cambridge. Question: Who has spoken the sentence 15? (A) User (B) System
Answer: (B) System

Sentence1: I have several options for you in the center of town. Do you have a price range in mind? Sentence2: You might be interested in the University Arms Hotel. Should I book you a room? Sentence3: Great! That is wonderful! Have a great day! Sentence4: I hope you have a wonderful day as well. Sentence5: I'm needing a place to stay that is in the centre of town. Sentence6: Indeed, they do! Sentence7: Just to verify, the University Arms offers free WiFi and free parking? Sentence8: Yes, the phone number is 01223351241 and the postcode is cb21ad. May I help you with anything else? Sentence9: I would prefer a hotel with 4 stars please, are either of those 4 stars with free parking? And also do either have free wifi? Sentence10: I don't care about the price range, but I need free parking, please. Sentence11: I have narrowed it down to 4 options. I have 2 cheaper ones that are guesthouses, and 2 expensive hotels. Do you have a preference? Sentence12: I don't want to book it right now. Can I get the phone number and postcode, please? Question: Who has spoken the sentence 6? (A) User (B) System

Answer: (A) User