You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.

Sentence1: I'm sorry... are you staying with two people for two days, or alone for five days? Which days would you like me to reserve? Sentence2: Can you suggest one for me please. I need the postcode, entrance fee if any and phone number Sentence3: You're welcome! Have a great day! Sentence4: Never mind the booking. I need a taxi. Sentence5: Great, that's all I need...thanks so much! Have a great day! Sentence6: The taxi is all set, look for a grey toyota, they can be reached at 07596698267 if there are any issues. Any other questions? Sentence7: the fitzwilliam museum is a museum is free. Postcode: cb21rb. Phone: 01223332900. Sentence8: The Fitzwilliam Museum is my destination. Sentence9: Can you book a room there for 2 people and two nights? I'll need a reference number as well. Sentence10: Also looking for a 4 star hotel in the same area as the museum. Sentence11: What is your destination? Sentence12: Thank you that's all I needed today. Sentence13: can you recommend a good place to go in the centre? Sentence14: I want to leave the hotel by 20:00. Sentence15: you are welcome all the time Sentence16: Okay what time do you need the taxi? Sentence17: i will be staying for 5 days Sentence18: What day will you be staying? Sentence19: Yes! What type of attraction would you like to visit? Sentence20: We have the University Arms, which is an expensive hotel, or the Alexander B&B, which is a charming, but inexpensive, guesthouse. Question: Who has spoken the sentence 9? (A) User (B) System
Answer: (B) System