Respuesta :

I think the answer is C. Merchants

Answer: c. Merchants

Explanation:

Yam was the name given to the route through the Mongol Empire. It was mainly used as a messager system to speed up the information about the Mongol armies. The journey stations were also used by the merchants. At the beginning it was available to merchants free of cost but as they abused of this possibility then they were required to pay for the services.