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

Example input: 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
Example output: Answer: (A) User
Example explanation: The sentence 1 is said by a user because the intent of it says that the information has to be gathered from the system
Q: Sentence1: There are so many to choose from. Any idea what kind of attraction you would like to visit? Sentence2: It will just be a table for one. Go ahead and book it Sentence3: Yes, I would like to go to a college with free admission. Sentence4: How many will be at your table? Sentence5: sure thing it is cb23bu, anything else today? Sentence6: Yes, I'd like to find a cheap Chinese restaurant. Sentence7: The reference # is 4ZBQs5GE . Need anything else? Sentence8: There are 10 colleges in the centre with free admission. Would you like me to suggest one? Sentence9: I'm looking for an attraction in the centre. Sentence10: What is that college's postcode? I'm also hungry and want somewhere to eat. Sentence11: Great, that's all I need...thanks so much! Have a great day! Sentence12: There are four options, charlie chan is in the centre near the college that you are visiting, shall I book you? Sentence13: Yes please book it for monday at 11:15 Sentence14: Can you give me the postcode for Christ's College? Sentence15: You are welcome. Glad to be of assistance. Enjoy your stay in Cambridge. Bye. Sentence16: Christ's college have a free entrance Sentence17: I also need a taxi that will arrive by the booking time. Sentence18: Booked car type : white ford Contact number : 07018249902 Question: Who has spoken the sentence 15? (A) User (B) System
A:
Answer: (B) System