1, A stands for national chain brands, including McDonald's, Burger King, Xicha, etc., and adopts in-store service.

2. B represents local businesses with high unit price such as flowers and cakes, and provides pick-up and delivery services.

3, C stands for individual users, and besides taking delivery, it also provides the service of helping to buy.

4, D stands for landing distribution, that is, the order distribution business of SF Express is provided.