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: Thanks so much, that is all I need. Sentence2: Are there any entertainment attractions in the south? Sentence3: Can I have the address, phone number, and entrance fee of Nusha. Sentence4: Thank you, goodbye. Sentence5: i also want a taxi to commute between the 2 places Sentence6: Your table is reserved, ref#39W1D7PP . Can I help you with anything else today? Sentence7: Is it in the same area as Nusha? Sentence8: I've booked you a taxi from nusha to the lucky star, arriving at 14:00. The car will be a white bmw. Contact number : 07301865482 Sentence9: I would like a chinese restaurant, please. Sentence10: Could you book me a table on Thirsday. 2 people at 14:00 Sentence11: There are two that fit your request. One is Nusha on Clifton Road and the other is Tenpin on Clifton Way. Do you need more information? Sentence12: Yes it is in the same area. Sentence13: There are 15 that I have found! What type of cuisine would you like? Sentence14: Thank you, you too. Sentence15: I will go ahead and book that now. Sentence16: Okay, great. Have a nice day. Sentence17: I can call for that. But thanks anyway. I am also looking for a cheap place to eat. Sentence18: Thank you. Can I please have the reference number? Sentence19: The address of Nusha is unit g6, Cambridge leisure park, Clifton road and their telephone number is 01223902158, but unfortunately, I do not have information on their entrance fee. Sentence20: There is one cheap Chinese restaurant in the area called The Lucky Star. Would you like me to book a reservation for it? Question: Who has spoken the sentence 19? (A) User (B) System
Output:
Answer: (B) System