A "best practice" refers to a $\_\_\_\_\_\_$

A$.$ policy or procedure that is unusually effective.

B$.$ method of performing an activity or business process that consistently delivers superior results compared to other approaches and that at least one company has demonstrated works particularly well in terms of delivering operating excellence.

C$.$ strategy$-$critical activity that results in sustainable competitive advantage.

D$.$ value chain activity that is a company's distinctive competence.