Detailed Instructions: You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Q: Sentence1: Certainly, at what time? And how many will be in your party? Sentence2: I have the caffee uno located in the centre. Sentence3: I am looking for a place to stay Sentence4: I also need a restaurant that serves venetian food, in the expensive range. Sentence5: Sounds good. Can you book for Wednesday for 1 person, 4 nights? Sentence6: Thank you for using the Cambridge TownInfo centre. Have a great day. Sentence7: There are are lots of options. Is there a particular side of town you would like to stay in? Sentence8: I'm looking for something moderately priced in the west. Sentence9: Are they 4 star rated by chance? Sentence10: Awesome. Now please book me a taxi to the restaurant. Just please make sure I get their in time for my reservation Sentence11: Thank you so much for all your help. Have a great day. Sentence12: The booking was successful, your reference number is N7L47L69 . Sentence13: Your taxi has been booked. It will be a white Volvo and their contact number is 07236170295. Sentence14: I am sorry I have no listings for any with 4 stars. Sentence15: That's okay. Can you look for one that is expensive? Sentence16: Please to book a taxi I need departure location, arival location and travel time. Please provide that information. Sentence17: Great! I would like a reservation for Wednesday. Sentence18: Table for 1 at Caffe Uno is confirmed for Wednesday at 18:15. They will hold your table until 15 minutes after your reservation time. Your confirmation number is A3L9KQ34 . Sentence19: the huntingdon marriot hotel is great! Sentence20: I will be leaving the restaurant. Sentence21: I'm sorry, I can't find any restaurants matching your request. Would you like to try for a different type of cuisine perhaps? Sentence22: The same group of people discussed at 18:15 the same day. Sentence23: OK, then please try Italian restaurants. Sentence24: In order to book a taxi I need the travel time, departure location and the arrival location. Sentence25: Yes, I will be leaving from the hotel. I will need to arrive at the restaurant by 18:15 on Wednesday. Sentence26: Hobsons House is exactly what you're looking for. Would you like me to book it for you? Question: Who has spoken the sentence 19? (A) User (B) System
A:
Answer: (B) System