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

Sentence1: Honestly, I am not sure. Which ones do you show available? Sentence2: I was able to reserve that for you. Your reference number is 439GP4J5 . Is there anything else I can assist you with? Sentence3: Can you make a reservation at Loch Fyne's for 4 people at 14:30 on sunday? Sentence4: We certainly have plenty expensive places in the center of town! What type of cuisine are you looking for? Sentence5: We have just about anything you can think of, from Loch Fyne's seafood to Bedouin's African. Sentence6: Thanks so much. That is all I need. Have a great day. Sentence7: I'd like to find an expensive restaurant in the centre of town. Sentence8: You as well, enjoy your meal! Question: Who has spoken the sentence 4? (A) User (B) System
Answer: (A) User