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

Sentence1: Okay I've done that for you. Your reference number INEQVBMN . Sentence2: I have the TR3177 train leaving at 09:50 on Sunday, would that work? Sentence3: Thank you. I am also hoping to book a train to Cambridge from Ely. Sentence4: You're quite welcome, have a lovely day! Enjoy Cambridge! Sentence5: That is all I need today. Thank you for all of your help. Sentence6: its been our pleasure to serve you. Sentence7: As long as it's a museum in the west, I'm happy. Can you pick one and give me the postcode? Sentence8: How about TR0718? It leaves at 09:50. Sentence9: That would be perfect, can you book that for one and give me the reference number please? Sentence10: I actually need to leave on Saturday. Is there something leaving at a similar time? Sentence11: I need to leave for Ely sometime after 8:30 on Saturday. Sentence12: Yes there are many. Do you have a preference for type? Sentence13: cafe jello gallery is a museum in the west. Its postcode is cb30af. Sentence14: What day and time would you like to travel? Sentence15: Hi there. Can you help me find a museum in the west part of town? Sentence16: Thank you, have a good day! Question: Who has spoken the sentence 5? (A) User (B) System
Answer: (B) System