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

Sentence1: The first train leaves at 5:59. Sentence2: Will you book it for me? Sentence3: Will this be for Monday also? Sentence4: I would be happy to book for you, how many tickets will you need? Sentence5: There are 49 train options and the price is 16.60 pounds. Sentence6: I am looking for the missing sock. Sentence7: Ok, all set. The table will be reserved for 15 minutes and your reference number is UT72J030 . Is there anything else I can help you with? Sentence8: Hello! Can you help me find a particular restaurant? Sentence9: The Missing Sock is located at Finders Corner Newmarket Road in the east. Phone is 01223812660. Sentence10: I sure can. If you bump your time back an hour there is a discount. Would you be interested in that? Sentence11: No thank you. Can you try to keep it at 17:45 unless its unavailable. And can I get a reference number please. Sentence12: TR3602 arrives at london liverpool street by 17:27, if that is cutting it too close the next closest is TR1764 arriving by 15:27. Sentence13: Sure, is there a particular cuisine you're looking for? Sentence14: Thanks, I also need a train departing from Cambridge and going to London Liverpool Street and need to arrive by 17:30. Sentence15: As long as it arrives by 17:30 and meets the other criteria you can choose. Sentence16: That might be a little early. Can you find something that arrives clsoer to 17:30? Sentence17: Can you book The Missing Sock for 5 people on Monday at 17:45? Sentence18: I hope you enjoy your stay. Sentence19: just one ticket. Sentence20: Yes, Monday and please provide the price. Sentence21: No, that will be all for me. Thank you and have a nice day!! Sentence22: You are set, the total fee is 16.6 GBP payable at the station . Reference number is : 7FGNO098 ., any other questions? Question: Who has spoken the sentence 6? (A) User (B) System
Answer: (A) User