Q: You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Sentence1: Hi. I am looking for a hotel to stay in. Sentence2: Thanks for serving me! Sentence3: Is there an expensive hotel with 3 stars that is located in the south? Sentence4: Yes, where will you be departing from? Sentence5: I have options available would you like me to book something for you. Sentence6: Do you have a hotel in mind or a price range? Sentence7: Yes. I'm looking for a 3 start hotel Sentence8: Your welcome. Have a great day! Sentence9: Can you locate a train that will take me to the hotel. Sentence10: I'd like to leave after 13:00 on Sunday and I want to go to Kings Lynn. Sentence11: You too much appreciated. Sentence12: Glad to be of service. Goodbye. Sentence13: I just need the train ID, please. Sentence14: Yes, there is the lensfield hotel. Sentence15: I recommend the gonville hotel located in the centre of town. Would you like me to book you a room or do you need anymore information? Sentence16: I was able to book your room per your request. The reference number is : 9RXKQ7C3 . Sentence17: I wanted somewhere expensive :D Sentence18: Sure thing TR7423. Thank you Sentence19: book it for 1 people and 2 nights starting from saturday. Sentence20: there are five expensive hotels in cambridge. Do you have a star preference or area in mind? Sentence21: What is your destination, and what time would you like to leave? Sentence22: The train should depart from cambridge and should leave on sunday. Question: Who has spoken the sentence 12? (A) User (B) System
A:
Answer: (A) User