You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.

Sentence1: I am looking for a restaurant. The restaurant should be in the south and should be in the cheap price range Sentence2: Thanks, that's all. Good bye. Sentence3: Is that restaurant in the south? I"d like to book for 4 people at 1330 on saturday please Sentence4: Nandos is indeed in the south. The booking is successful with the reference number PCFFZ610 . Do you need more help? Sentence5: How about nandos, I've heard great things! Sentence6: You are more than welcome! Question: Who has spoken the sentence 1? (A) User (B) System
Answer: (B) System