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

Sentence1: No that's okay, I just wanted to learn about it. Thanks! Sentence2: No, not at this time. Thanks for your help. Sentence3: We have 23 guesthouses offering free WiFi. Do you have other preferences, as well? Sentence4: I'm looking for a guesthouse with free wifi. Sentence5: You're quite welcome. Thanks for contacting the Cambridge TownInfo Centre and have a great day! Sentence6: A and B Guest House has a four-star rating, and their postcode is cb12dp. Would you like me to book that for you? I should mention there's no parking. Sentence7: A and B guest house is available. Sentence8: Something in the east, please. Sentence9: That sounds like it will work. Do they have a star rating? If so, can I get the postcode. Sentence10: You are welcome. Do you need additional information about restaurants or attractions? Question: Who has spoken the sentence 9? (A) User (B) System
Answer: (B) System