A Firm Is Said to Be Vertically Integrated If

A firm is said to be vertically integrated if:

A) its subsidiaries are involved in the production of variants of the same product or service.
B) its competitors are in the same stage of production and in the same industry.
C) it acquires a majority stake in a competing firm in its own industry.
D) its stock value has been increasing at a higher rate than its competitors' for at least one quarter.
E) it owns several layers in its value chain.