SEU Resources And Capabilities For Formulating Strategy Discussion

I’m working on a management question and need the explanation and answer to help me learn. Discuss which should be the primary basis for formulating strategy: The external market or the internal environment (firm’s resources and capabilities)? Share an example of a company whose strategy has been based upon the external market and one that is based on a set of capabilities.Discuss how the external environment or resources and capabilities offer a sustainable competitive advantage and generate profit in each case.