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

Sentence1: Can you book me a table for 3 people at 20:00 on Wednesday? Sentence2: Hi, I'm looking for a particular restaurant named Bedouin. Can you help? Sentence3: Booking was successful. The table will be reserved for 15 minutes. Reference number is : N332O6JK . Sentence4: Great, thank you so much. That'll be all for today. Bye! Sentence5: Thank you for calling the Cambridge TownInfo centre, have a great day. Sentence6: Yes. Bedouin serves african food and is is located in the centre. Question: Who has spoken the sentence 4? (A) User (B) System
Answer: (A) User