Definition: You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Input: Sentence1: Thanks. That's all I need. Good-bye. Sentence2: Sounds like it. What is that travel time exactly? Sentence3: That narrowed it down a bit. Do you have a preference on the price range? or the type of accommodation? Sentence4: Acorn guest house , the phone number is 01223353888. Sentence5: Depart does not matter but I need it to arrive by 12:45. Sentence6: Thanks and enjoy ! Sentence7: 60 minutes is the length of the train ride Sentence8: Thanks, I also need to train form broxbourne to cambridge on sunday. Sentence9: I'm looking for a place to stay. Can you help me find one? Sentence10: I would like to stay in the north. Wi-fi and at least four star reviews are also important. Sentence11: What time would you like to depart? Sentence12: What area of town would you prefer? Sentence13: I have train TR6774 that leaves at 10:32 and arrives in Cambridge by 11:32. Will that work for you? Sentence14: Not really, no. Can you give me the phone number for your favorite place? Question: Who has spoken the sentence 4? (A) User (B) System
Output:
Answer: (A) User