You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Q: Sentence1: No, that's all for today. Thank you! Sentence2: What is your departure day and time? Sentence3: I have no set departure time as long as my arrival time is before or at 19:00. Sentence4: Ok, there are 13 different options, if you give me a departure time, we can narrow it down from there. Sentence5: I don't need to book at the moment, thanks. All I need is the ticket price. Sentence6: Yes, may I please have the address, postcode, and phone number for the ADC Theatre? Sentence7: There are 4 theatres in the center - adc theatre, cambridge arts theatre, mumford theatre, and the cambridge corn exchange. Would you like more information on any of those? Sentence8: No I would like to go somewhere in the centre. Is there a theatre of any type? Sentence9: Great, thanks. I also need to book a train going to cambridge, and I will be departing from broxbourne. Sentence10: Thank you for using our site and let us know if you need anything else in the future. Sentence11: The ADC Theatre is in postcode cb58as and is located on Park Street. The phone number is 0122300085. Sentence12: The price of TR1828 from Broxbourne to Cambridge is 17.90. Is there anything else I can help you with? Sentence13: I am looking for places to go in Cambridge. I am looking for an attraction that has sports and located in the Centre, can you help me find it? Sentence14: TR1828 will get you in at 18:32. You leave at 17:32. May I book that for you? Sentence15: I would like to leave on Thursday and arrive by 19:00. Sentence16: Okay. Do not hesitate to call us back if you need anything else. Sentence17: It doesn't look like such a place exists. Would you like me to look outside of the city centre? Sentence18: Alright. Goodbye. Question: Who has spoken the sentence 1? (A) User (B) System
A:
Answer: (B) System