Instructions: You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Input: Sentence1: I'd like some help finding a train leaving peterborough on tuesday. Sentence2: I have train TR1674 leaving at 10:48 and arriving at 11:38. Would you like to book tickets? Sentence3: OK, is it going to Cambridge? Can I have the reference number please? Sentence4: Unfortunately, there are no trains that leave after 10:15. Sentence5: Okay. Your train booking was successful. You'll owe 16.5 which can be paid at the station. The reference number is X58GNQ74 . Sentence6: I have it right here Sentence7: Okay what are the available train times? Sentence8: Leave after 10:15, please. Sentence9: The address is 138 perne road. Would you like to book a room? Sentence10: I need a train from Peterborough to Cambridge on Tuesday, leaving after 10:15. Sentence11: Have a nice day. Sentence12: there seems to be a break down in communication. Please restate the departure and arrival locations and the day and time. Sentence13: Absolutely, do you want to leave or arrive by a certain time? Sentence14: it is 138 perne road. Sentence15: i have booked you one leaving at 10.19. Sentence16: Can you look up a hotel called Carolina bed and breakfast? Sentence17: No, I just need the address. Thank you. Sentence18: I need to book for one person, I will need the reference number. Also, I need to book a hotel called Caroline Bed and Breakfast, I need the address. Sentence19: Well, thats great. That means you should be able to give me the address Sentence20: Thank you, have a wonderful day. Let us know if we can help in any way. Question: Who has spoken the sentence 4? (A) User (B) System
Output:
Answer: (A) User