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

Sentence1: Great, your reference number is K3TPR6UI . Anything else? Sentence2: yes, how about another restaurant in the same area and price range? Sentence3: Great! I would like to book a table for 1 at 18:15 on Friday. Sentence4: I was unable to reserve a table at that time. Would you like me to find another restaurant? Sentence5: I'm looking for cafe uno, can you help me find where it is? Sentence6: That sounds good as long as it's in the same area and price range. I'll need the reference number too please. Sentence7: How about Bedouin, they serve African Cuisine. Sentence8: No thank you. Good bye. Sentence9: You're welcome. Good-bye. Sentence10: Absolutely! Caffe uno is located at 32 Bridge Street City Centre. Question: Who has spoken the sentence 9? (A) User (B) System
Answer: (B) System