You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Q: Sentence1: The tickets are 8.08 pounds per ticket. Would you like to book the train? Sentence2: No, that's all I need right now. Thank you! Sentence3: How much is the ticket? Sentence4: Yes. I need to leave on Sunday and arrive by 17:15. Sentence5: Not at the moment. Thank you. Sentence6: You're welcome. Have a wonderful day. Sentence7: There are 133 trains that make that trip, do you have a day and time? Sentence8: I have train TR7744 that leaves the airport at 16:24 and will get you there by 16:52. Would you like me to book you a ticket? Sentence9: I need a train from stansted airport to cambridge, please. Sentence10: Can I help you with anything else? Question: Who has spoken the sentence 4? (A) User (B) System
A:
Answer: (A) User