You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Q: Sentence1: I'm looking for a Russian restaurant in the centre. Sentence2: No that will be everything I needed for today. Thank You! Sentence3: I would like the one closest to the alexander bed and breakfast please. Sentence4: The alexander bed and breakfast is available and in the cheap price range. Sentence5: You're welcome. Enjoy your stay in Cambridge. Sentence6: I'm sorry, but there are no Russian restaurants in all of Cambridge. Would you like to try a different type of cuisine? Sentence7: Great! I was able to book that for 4 people and your reference number is F6FSFJ75 . Anything else I can help you with? Sentence8: OK, book that for 4 people. We'll arrive monday and stay 4 nights. And can I have the reference number? Sentence9: The Gardenia is priced cheaply and its psot code is cb23ll. Sentence10: How about the gardenia? Sentence11: I am looking for a place to stay. Preferably a guesthouse with free parking included. Sentence12: Can you provide me with the price range for the Gardenia as well as the postcode? Sentence13: I would like the hotel to be expensive. Sentence14: How about a cheap one? Sentence15: We have 21 entries that match your search. Do you have any other preferences? Sentence16: Yes, I have found three restaurants matching your inquest. Sentence17: We don't have any expensive guesthouses. Would you like to try a hotel or a guesthouse in a different price range? Sentence18: Is there a Mediterranean restaurant in the centre? Sentence19: Thank you for the information Sentence20: Is there anything else I could assist you with? Would you like help making a reservation? Question: Who has spoken the sentence 5? (A) User (B) System
A:
Answer: (B) System