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'm looking for a restaurant that serves spanish food Sentence2: Thank you for using our system. Good bye Sentence3: The address for La Raza is 4 - 6 Rose Crescent. Would you like their phone number? Sentence4: no, thank you Sentence5: La Raza is a Spanish restaurant, it is in the cheap price range, and it is located in the centre part of town. Would you like the phone number? Sentence6: What is the address? Question: Who has spoken the sentence 4? (A) User (B) System
Answer: (A) User