Business model is the key to the long-term development of enterprises. Start-ups should pay attention to the creation of business model and constantly improve the business model to make it an effective profit model. Which of the following statement about the business model is wrong? A、Free is a business model. Once established, as long as there are enough users, enterprises do not need to consider how to make profits. B、Start-ups need to find ways to make the transfer cost of customers high. The higher the transfer cost of customers, the more loyal customers are, and they will not leave easily. Such a business model is more likely to succeed. C、A start-up company in a new retail industry improves the efficiency of the supply chain through Internet of things, big data and other technologies, innovates its business model at a lower cost than its competitors, and makes profits one year later. It can be considered that the company has successfully built a profit model. D、At present, most of the learning guidance platforms are Professionally-Generated Content (PGC) mode. A college students’ entrepreneurial team takes “how to let users work for you” as the starting point of thinking, transforms the PGC mode into the User Generated Content (UGC) mode, and constructs the UGC mode of college students’ work mutual assistance platform, which can be considered as the improvement and promotion of the existing business model.