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: What time would you like? Sentence2: Unfortunately, after trying to book again I was still unsuccessful. Would you like to try another day or time? Sentence3: Could you please try 18:00 on the same day? Sentence4: There are 202 trains to cambridge on Saturday. Can you tell me your departure station and the time you'd like to travel? Sentence5: I'd like the table for 19:00, please. Sentence6: Great, all I need is the reference number please. Sentence7: I would like to make a reservation for 6 people on Saturday. Sentence8: I would like to leave from stansted airport after 15:00 Sentence9: I would maybe be interested in booking this train. What is the train id, price per ticket and arrival time? Sentence10: can you book me a train to Cambridge that leaves on Saturday. Sentence11: I unfortunately do not have this info for you. The booking is now saying unsuccessful. Sentence12: That is all. Thank you. Sentence13: Okay. I have made a reservation for Saturday at 19:00 for six people. Sentence14: Can you try again please? Sentence15: Have a great day. Sentence16: Okay thanks, I also need info for the cow pizza kitchen and bar. Sentence17: Your booking for Saturday at 18:00 was made. Your reference number is L7W1NACD . May I help you with anything else today? Sentence18: The train is TR1493 with the price 8.08 pounds. The arrival time is 15:52. Sentence19: I found nine trains leaving stansted airport for cambridge, leaving every hour starting at 15:24. Would you like to book that first train? Sentence20: Ok. That's a moderately-priced gastropub in the centre. Would you like the address or phone number? Question: Who has spoken the sentence 4? (A) User (B) System
Solution:
Answer: (A) User