Definition: You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Input: Sentence1: You're welcome. Can I help you with anything else? Sentence2: That is all. Thanks Sentence3: The post code is CB11JG. Sentence4: Thank you, what's the post code? Sentence5: Thank you for your help Sentence6: Cambridge, parkside police telephone number 01223358966. Sentence7: I need to get to the nearest police station, can you assist me? Sentence8: Okay. Have a good day and thanks for using our system. Question: Who has spoken the sentence 4? (A) User (B) System
Output:
Answer: (A) User