The death of Kublai Khan in 1259 marked a major turning point because up to his death, the Mongol Empire was more or less constantly expanding. However, with his death, things started becoming worse and worse eventually as the empire became to big for one emperor to hold it.
The page when nobody could find him
Vertical integration is a form of business organization in which a company controls the supply chain from acquisition of raw materials, to manufacturing, to end sales. In history, vertical integration was a form of industrial organization. One common effect of vertical integration was that it made supplies more reliable and thus, improved efficiency. It took over and controlled the quality of the product at all stages of production
I think it might be B. Hope this helps
