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

[EX Q]: Sentence1: 5 nights, please. Sentence2: Sure. Please book five tickets for me and reply with the reference number. Sentence3: It's booked and your reference number is LFE8G8CE . The address is 154 chesterton road and postcode is cb41da. Anything else I can do for you? Sentence4: Where will you be departing from? Sentence5: Enjoy your visit. Please give us a call if you need further assistance. Sentence6: 5 people starting on Sunday. Sentence7: Yes, what area would you like to stay in? Sentence8: Great, let's book that one. Please send me the address, postcode and reference number. Sentence9: Booking was successful, the total fee is 22 GBP payable at the station. Reference number is : BUBQRD4R . Sentence10: Yes I also need a train that leavers after 12:00 going to ely. Sentence11: There is the Acorn guesthouse in the moderate price range and 4 stars. It also has free wifi and parking. Sentence12: There is no train leaving 12:00, but train TR5484 leave 13:50 do you want to adjust your time? Sentence13: Don't care. but I'd like a place that's Moderately priced and offers free WiFi. Sentence14: East London. Thanks Sentence15: How many days do you plan on staying? Sentence16: That is all I need, good bye. Sentence17: How many people would you like it booked for and for what days please? Sentence18: Hi, I am hoping to find a 4 star hotel room. Can you recommend one for me? Question: Who has spoken the sentence 9? (A) User (B) System
[EX A]: Answer: (B) System

[EX Q]: Sentence1: Maybe you could try again? Sentence2: I am looking for a place to stay in cambridge in the moderate price range with 4 stars Sentence3: I found the restaurant you want. Do you want me to make reservation? Sentence4: I am having a hard time booking this, could I make sure the place you would like is the Pizza Express at Fen Ditton? Sentence5: There are 11 matches. Do you have a preference for hotel types? Sentence6: Yes, for 5 people on Friday around 13:45, please Sentence7: I am not able to book anything right now. Sentence8: Okay....well I'm over here waiting....don't forget the reference number too Sentence9: I will go ahead and book that for you now. Sentence10: Thanks for the room booking. Can you locate a restaurant for me, too? The name is pizza express Fen Ditton. Sentence11: The booking worked this time! The reference number is S31A87TV . Anything else today? Sentence12: No problem. If you need anything else just call us back. Sentence13: Yes it is, but if 13:45 time isn't working then 12:45 would also be acceptable. Sentence14: Great, thanks for your help! Have a good one. Sentence15: You have a room booked at the Warkworth House (ref# TP8X26LA). Can I help you with anything else? Sentence16: No, but it should be in the east. Sentence17: I have 3 guesthouses matching your request. Do you care about parking? Sentence18: Pick one and book me for 5 people lasting three nights starting Friday please. Question: Who has spoken the sentence 15? (A) User (B) System
[EX A]: Answer: (B) System

[EX Q]: Sentence1: Yes please book the Hamilton Lodge. Sentence2: Yes, that will be fine. Sentence3: No that will be it. Thank you. Sentence4: Does the The Hamilton Lodge have both free wifi and free parking? Sentence5: The Hamilton Lodge would be perfect! It is a moderately priced 3 star guesthouse on the north side of town. Does that sound okay to you? Sentence6: I am looking for a guesthouse to stay at that has free wifi. Sentence7: Ok. Were you hoping for a particular price range or part of town? Sentence8: Great. Thanks so much for your help. Sentence9: What night would you like me to book for you, and for how many people? Sentence10: Okay. I was ablt to book you into there and your reference number is O4BPEOXQ . Sentence11: Is there anything else I can help you with today? Sentence12: I don't care about the part of town or the price range, but it needs to be a three star hotel. Sentence13: You are welcome. Enjoy your stay in Cambridge! Sentence14: I am sorry, the Hamilton is already booked. Would you be interested in the Bridge Guest House instead? It is the same as the Hamilton but is in the Southern area. Sentence15: Wednesday, 6 people, for five nights, please. Sentence16: Yes, it does. Do you want to make a reservation? Question: Who has spoken the sentence 3? (A) User (B) System
[EX A]:
Answer: (B) System