Definition: You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Input: Sentence1: Many trains leave Cambridge around 20:45, what is the destination? Sentence2: Thanks, that's all. Good bye. Sentence3: welcome again some other time Sentence4: I need to get to london liverpool street. Sentence5: I would like to leave on Thursday Sentence6: Train TR3695 leaves 21:59 and arrives on 23:27. Would you like to book it? Sentence7: I have several options for you, and the price and exact departure time varies by day of the week. Do you have a day preference? Sentence8: I need help finding a train leaving Cambridge after 20:45. Question: Who has spoken the sentence 3? (A) User (B) System
Output:
Answer: (B) System