Technology diffusion is the application and promotion of innovative technologies in other economic fields and a larger geographical space. From a geographic perspective, technology diffusion is the spatial flow and transfer of technology. It consists of new technologies and suppliers, recipients, and delivery channels. According to the above definitions, which of the following is technology diffusions? ['Multiple pharmaceutical factories in a province use the same long-recognized formula to produce a drug.', 'City A has developed its own characteristic industry by drawing on the innovative industry technology of City B.', "A company's production ideas are applied to its own artistic creation by a foreign artist.", "Employees of a company's R & D department reveal their core R & D secrets to the company's competitors."]