You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.

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
Solution: Answer: (A) User
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

New input: Sentence1: Yes. Book for 2 people for 4 nights on thursday and I'll need the reference number too please Sentence2: Okay, great! Enjoy your day. Sentence3: I have your table for 2 booked at the Bedouin. Would you like anything else? Sentence4: Your booking was successful. Your reference number is Q5BKFIC3 Sentence5: The reference number is 0LG9G1BT . Is there anything else I can help you with? Sentence6: We have one restaurant, the Bedouin. Would you like me to make you a reservation? Sentence7: I need the reference number too please. Sentence8: 2 people for Thursday at 19:00 please Sentence9: I was unable to find anything matching that. Would you like to try again? Sentence10: How about African food in general? Sentence11: yes please. Sentence12: The Limehouse is a moderately priced guesthouse on the north side of Cambridge. They are a 4-star establishment and offer free parking and Internet. Would you like to make a reservation? Sentence13: Thank you. Can you find us some good eats, too? We'd like something moderately priced that serves South African cuisine. Sentence14: I would be happy to book a reservation for 2. What day are you looking at and time? Sentence15: I am looking for a hotel in the Cambridge area called the limehouse. Sentence16: Thank you that is all I need. Question: Who has spoken the sentence 14? (A) User (B) System
Solution:
Answer: (A) User