You will be given a definition of a task first, then some input of the task.
You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.

Sentence1: that sounds great. Could you make a reservation at 16:00 for 2 people this Saturday? Sentence2: I have Backstreet Bistro and The Cow Pizza Kitchen Bar. They both serve gastropub food. Which one do you prefer? Sentence3: I am looking for a restaurant called the Slug and Lettuce. Sentence4: Okay. Glad I could help. Sentence5: Nah, either one is fine. I need a reference number though. Sentence6: I found a listing for the Slug and Lettuce. The address is 34 - 35 Green Street in the center of town. It serves gastropub food. Sentence7: Ok, I have booked you at the backstreet bistro. Reference number 42VFS0SM . Is there anything else I can help you with? Sentence8: That will be all. Thank you for your help! Sentence9: Yes, is there anything else in the same vicinity and the same general price range? Sentence10: Unfortunately the booking was unsuccessful, would you like to try a different restaurant or different day and time? Question: Who has spoken the sentence 7? (A) User (B) System
Output:
Answer: (B) System