Q: You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Sentence1: Have a nice day. Sentence2: Are there any boat attractions? Sentence3: And what time would you like to leave? Sentence4: Where are you departing from and what day are you travelling on? Sentence5: I have the cmbridge punter boat located in the centre. Sentence6: How about the Funky Fun House or Cherry Hinton Hall and Grounds in the east? Sentence7: The TR4651 train leaves Bishops Stortford at 15:29. Would you like me to book you a seat on it? Sentence8: Can you make a suggestion? Sentence9: Yes, it does. Sentence10: Thank you. I also need to find a place to go in the centre of town. The type of attraction should be entertainment. Sentence11: There are no entertainment areas in the centre, any other preferences? Sentence12: What is the price for the train ticket? Sentence13: I need a train going into Cambridge, arriving by 17:45. Sentence14: Thank you for using the Cambridge TownInfo centre. Cheers! Sentence15: That sounds great. Can I get the phone number, address, and entrance fee? Sentence16: Is there anything else I can assist you with today? Sentence17: Does it arrive in Cambridge by 17:45. That is the most important thing. Sentence18: The price is 8.08 pounds. Sentence19: Unfortunately, I don't have information on the entrance fee, but you can call them at 07807718591 to find out. The post code is cb41as Sentence20: I am leaving from Bishops Stortford on Sunday. Sentence21: Okay thank you for your help. Sentence22: I would prefer to leave at 15:00. Question: Who has spoken the sentence 21? (A) User (B) System
A:
Answer: (B) System