You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.

Let me give you an example: Sentence1:i need a place to dine in the center thats expensive Sentence2: I have several options for you; do you prefer African, Asian, or British food? Sentence3: Any sort of food would be fine, as long as it is a bit expensive. Could I get the phone number for your recommendation?Question: Who has spoken the sentence 2? (A) User (B) System
The answer to this example can be: Answer: (A) User
Here is why: The sentence 1 is said by a user because the intent of it says that the information has to be gathered from the system

OK. solve this:
Sentence1: I also need a train from stansted airport and go to cambridge. Sentence2: Can you help me find information on a hotel called allenbell? Sentence3: That is all I need. Good bye. Sentence4: I need a room there for 8 on saturday, and staying two nights, I'll need the reference number too please Sentence5: Thank you for using our service! Sentence6: Booking was successful, the total fee is 80.8 GBP payable at the station . Reference number is : 2D2L9TYI . Sentence7: Train TR5921 departs from stansted airport at 18:24 and arrives at cambridge at 19:30 on friday. Is there anything else I can help you with? Sentence8: 18:15 is the departure. 19:30 is the arrival. Sentence9: All trains leave on friday, what time is the depature and arrival? Sentence10: That will work. Please book 8 tickets. I'll also need a reference number. Sentence11: I've scheduled your booking at the Allenbell on Saturday for 2 nights for 8 people. The Reference number is : WBD98WJA . Sentence12: The Allenbell Hotel is a 4 star guesthouse hotel, the price range is cheap. Internet and parking are available. Would you like to book a room? Question: Who has spoken the sentence 6? (A) User (B) System
Answer:
Answer: (A) User