Answer:
b. Companies buy up all competition to form a monopoly.
Step-by-step explanation:
Horizontal integration is a term that refers to a corporate strategy, where a company buys or joins other companies in the same commercial sector and that work with the same products, creating a great company that can even provoke a monopoly in the productive sector, but its main objective is to strengthen the consolidation of the sector and total control of the production of a product.