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: there are three chinese restaurants. Would you like the phone number for all three? Sentence2: What is the phone number? Sentence3: no, that's all I need. thank you and goodbye Sentence4: They serve chinese food. Sentence5: Have a nice day! Sentence6: what is the food type of that restaurant ? Sentence7: I want a restaurant in the north part of town and serves chinese food. What is the phone number? Sentence8: golden wok is 01223350688, hakka is 01223568988 and the hotpot is 01223366552. Is there anything else I can help you with? Question: Who has spoken the sentence 4? (A) User (B) System
Answer: (A) User