Detailed Instructions: You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Q: Sentence1: Yes, please book it. I would also like the address. Sentence2: Departing from peterborough on friday. I should arrive by 10:00 Sentence3: I'd be happy to help. Can you tell me more about your trip? Where will you be departing from, and on what day would you like to travel? Sentence4: There are 8 entries that match that. Is there any time that you want to leave? Sentence5: The TR1662 leaves Peterborough at 05:19, arrives Cambridge 06:09. Care to book a ticket? Sentence6: There is one vietnamese restauarant in the area, would you like me to book that? Sentence7: And what time would you prefer to leave? Sentence8: Ok, the train was successfully booked. The total fee is 132 GBP payable at the station. Your reference number is: AYILO5E4 Sentence9: I am also looking for a restaurant in the west and in the cheap price range that serves korean food. Sentence10: You're welcome! Have a great day! Sentence11: Doesn't matter. Just pick one. Sentence12: I would like to arrive by 10:00 Sentence13: No thats all i wanted thank you Sentence14: Yes. Actually, I would like to book 8 tickets for that train, please. Sentence15: I just needed that info. Thank you. Sentence16: I need some help finding a train to Cambridge. Sentence17: There are no establishments that fit your specifications, unfortunately. Would you like to search for a different type of cuisine, or a different price range? Sentence18: The address is 17 Magdalene Street City Centre. How many people people and for what day and time? Sentence19: Is there anything else I can help you with today? Sentence20: Why don't you try vietnamese food. Question: Who has spoken the sentence 7? (A) User (B) System
A:
Answer: (B) System