When a company has become proficient in modifying, upgrading, or deepening the company's resources and capabilities in response to its changing environment and market opportunities, it is called:

Dynamic capability

Explanation:

Dynamic capability is the term which is defined as the ability or the capability of the firm or the business to reconfigure, integrate, upgrade, build or modify the external as well as the internal competences in order to address the rapidly changing environments.

Therefore, the dynamic capability is the term which is described as the companies become proficient in upgrading, build the resources of the company as well the capabilities in relation to the changing environment as well the market opportunities.