What are economies of scope?

a$.$ Complex sets of resources and capabilities that link different businesses, primarily through managerial and technological knowledge, experience, and expertise

b$.$ Cost savings a firm creates by successfully sharing resources and capabilities or transferring one or more corporate$-$level core competencies that were developed in one of its businesses to another of its businesses.

c$.$ The abilities of a firm to sell its products above the existing competitive level or to reduce the costs below the competitive level of its primary and support activities

d$.$ The advantages achieved when a company produces its own inputs or owns its own source of output distribution.