A core competence

a$.$ is typically results$-$based, residing in a company's tangible physical assets on the balance sheet.

b$.$ detracts from a company's arsenal of competitive capabilities and competitive assets and is not a resource strength considered to be genuine.

c$.$ is an activity that a firm performs proficiently that is also central to its strategy and competitive success.

d$.$ is often grounded in a single department's set of knowledge and expertise.

e$.$ is a proficiently performed external activity.