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

Sentence1: I am also looking for a train into cambridge the same day please Sentence2: Sorry. There are no moderately-priced 0 star places in the south of town. Do you want to try some other criteria? Sentence3: The booking was successful. Your reference number is 3UKMLIWO . Sentence4: It was a pleasure, thank you so much. Sentence5: Sunday as well, please. Sentence6: There are two places that match those requirements, one in the north and one in the city centre. Would you like to hear more about these? Sentence7: Okay. Can you purchase tickets for me. There will 6 of us. Sentence8: What day would you like the train? Sentence9: Yes, I need to leave Leicester after 11:00. Heading to Cambridge for the day. Sentence10: Hello, I'm looking for a place to stay that is moderately priced and a star rating of 0. Sentence11: Could you try for the center part of town? Sentence12: Are you sure there aren't any in the south of town? Sentence13: The cityroomz is a hotel in the centre part of town with a 0-rating in the moderate price range. Can I reserve a room for you there? Sentence14: Yes. Thank you for your help. Sentence15: I would recommend TR8285. It leaves Leicester at 11:09 and arrives in Cambridge at 12:54. Sentence16: Yes, I'd like to reserve it for 6 people for 4 nights starting Sunday, please. Sentence17: Your reservation was successful. Your reference number is SCKIYN5Q . You depart from Leicester at 11:09, arriving in Cambridge at 12:54. Would that be all for you today? Sentence18: Sure, where will you be departing from, and do you have a departure or arrival time? Question: Who has spoken the sentence 17? (A) User (B) System
Answer: (B) System