Given the task definition and input, reply with output. You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.

Sentence1: You're welcome, have a great day! Sentence2: I want a taxi between the hotel and Ugly Duckling in time for my booking. Sentence3: That is all I will need. Thank you. Sentence4: Price doesn't matter to me. Do you have any recommendations? Sentence5: I also need a taxi to commute between the two places. Sentence6: Please I need a place to Stay in Cambridge and I have the express by holiday inn Cambridge in mind. Can you help book that for me? Sentence7: I do! I'd recommend the Ugly Duckling. Would you like to book a table? Sentence8: I need a few more specifics before I can book that taxi for you. Sentence9: I also need a restaurant in the center of town that serves chinese food Sentence10: Yes, please book a table for 4 people at 12:15 on tuesday. Sentence11: That hotel is considered to be on the more expensive side. Sentence12: What price range were you considering? There are 10 Chinese restaurants in that area. Sentence13: I can help with that. When would you like to stay? Sentence14: we have booked white bmw and the contact is 07951264256 Sentence15: All srt, the reference number is GCSU8UZP Can I assist with anything else? Sentence16: I am not sure. Would you happen to be able to tell me the price range? Question: Who has spoken the sentence 12? (A) User (B) System
Answer: (A) User