Digital guest interactive management refers to the use of advanced electronic communication and network means to achieve efficient, direct, autonomous, and reciprocating communication between the enterprise and the target customer group, so as to meet the personalized needs of customers. Based on the above definitions, which of the following is interactive management? ["A city government has set up a mayor's mailbox on the official website to collect opinions from various quarters, answer mass inquiries in a timely manner, and work hard to improve government work.", 'A toy company establishes an online communication platform. As long as parents submit the required toy types, prices, functions, etc. to the platform, the company can produce them in a timely manner.', 'A furniture manufacturer collects massive data from the network, analyzes market demand, and adjusts furniture style in a timely manner.', 'According to the information provided by a water heater manufacturer, a water heater manufacturer regularly contacts the customer to provide customers with free maintenance services.']