Given the task definition and input, reply with output. You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.

Sentence1: The train should go to cambridge and should arrive by 14:00. Sentence2: Thank you, good bye. Sentence3: Yes departing from there heading to Cambridge on Saturday. Sentence4: Great! Have a nice day! Sentence5: I have train TR7309 departing London Kings Cross at 11:17 and arriving in Cambridge at 12:08. Sentence6: When would you like to depart London Kings Cross? Sentence7: Booking was successful, the total fee is 94.4 GBP payable at the station. Reference number is : 7UGGORNQ . Sentence8: Please book that for 5 people. Sentence9: I am looking for a train departing from london kings cross Sentence10: What time would you like to depart or arrive? Question: Who has spoken the sentence 1? (A) User (B) System
Answer: (B) System