sentences:  Food is sold in both open air markets and urban supermarkets, and by the late 1990s, China's farms were adapting to more specialized crop production as the local markets become more connected to the national and international markets.However, local authorities largely control food regulation enforcement unless the central government steps in.As urban consumers' incomes increase, the demand for quality food goods, safer production, and processed foods also increases, and urban residents and supermarkets attract more national and media attention to food problems.