Q: You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Sentence1: I'd like to stay in a guesthouse that offers free wifi. Sentence2: North area please. Sentence3: I want to leave the restaurant by 13:00 to go back to the hotel. Sentence4: What is your price range? Sentence5: thank you and enjoy your stay in cambridge Sentence6: I would also like some Italian food in the area. Sentence7: Yes, I need a booking for this tuesday please. Sentence8: Great, I have booked a room at this hotel to your required specifications. Your booking was successful and your reference number is 468MRI75 . Sentence9: Thanks for all your help. That's all I needed today. Goodbye! Sentence10: A reservation isn't necessary. Instead, please find me a taxi to get me there. Sentence11: My price range is moderate. Sentence12: Great. I have booked your ride. The driver will be in a grey Honda. The contact number is 07036773772. Sentence13: I would like to be able to leave the restaurant by 13:00, can you book a table that allows us the time needed to eat. I also need the address for the restaurant. Sentence14: No, but there will be 6 people in my party and we'd like to stay for 4 nights starting on Tuesday, if possible. Sentence15: Fourteen good choices for you, what part of town would you prefer? Sentence16: Do you want the reservations for 6 people on Tuesday? Also, does 11:30 sound good? Sentence17: The Acorn guesthouse come highly recommended, shall I book a room for you there? Sentence18: Where will the taxi be picking you up? Sentence19: that narrows it down to 8 options. any other preferences? Sentence20: I'll be happy to help with that! Da Vinci Pizzeria is located in the same area as the hotel. Would you like to book a table? Question: Who has spoken the sentence 19? (A) User (B) System
A:
Answer: (B) System