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: Yes it has free parking and internet. Sentence2: Yes please. The north side of town and only 4 star guesthouses please. Sentence3: Actually, I'll hold off on booking for the moment, but could I also get information about a taxi. Sentence4: I would like to leave the museum by 16:00, please. Sentence5: I found 24 guest houses for you. Any particular area you have in mind? Sentence6: The address is castle street and the phone number is 01223748100. Sentence7: That one sounds great. Can you give the address and hours? Sentence8: Sure, how many days will you be staying and how many people in the room? Sentence9: Ok to be clear what is your destination and your departure locations? Sentence10: There are 8 guesthouses on the north side of town. May I suggest Acorn Guest House or Arbury Lodge Guesthouse? Both are moderate price range with 4 stars. Which would you like? Sentence11: first of all does the guesthouse have free internet? That is important. First things first. Sentence12: Sure what would you like to know? Sentence13: Great, thanks! I also need a place to stay, I'd prefer a guesthouse. Sentence14: What time would you like to leave or arrive by? Sentence15: Please let us know if we can assist you in the future. Have a great trip to Cambridge. Goodbye. Sentence16: Sure, there are several. Most are free. My favorite one with free admission is Kettle's Yard on Castle Street. It is on the West side, is that area ok? Sentence17: Sounds great! I think I have everything I need now. Thanks for all your help. Sentence18: Okay. I need a taxi between the hotel and the museum. Sentence19: Yes expect a red Ford to pick you up and his contact number will be 07816413809. Sentence20: Don't you have access to my previous requests? It would be from Kettle's Yard to the acorn guest house and I need to leave by 16:00. Sentence21: Hi, I would like info about museums I could visit on the west side. Sentence22: The acorn please. can you book that? Question: Who has spoken the sentence 11? (A) User (B) System
Answer: (B) System