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: i want some mexican food. Sentence2: Dojo Noodle Bar serves asian oriental food and is located in the centre of town. The price range is cheap. Sentence3: The phone number for dojo noodle bar is 01223 363471. Would you like any other information? Sentence4: I don't care. Sentence5: You're welcome. Goodbye. Sentence6: We have four Asian oriental restaurants in centre. What price range do you prefer? Sentence7: What is the phone number? Sentence8: No, thank you, that's all I need. Thank you and goodbye! Sentence9: The only listing for Mexican food is Chiquito Restaurant Bar. How else may I assist you? Sentence10: I want a restaurant in the centre and serves asian oriental food? What is the phone number? Question: Who has spoken the sentence 9? (A) User (B) System
Answer: (B) System