What factor allowed the incas to use their military efficiently? they developed an extensive system of paved stone roads. they created a unique record-keeping system for military campaigns. they adopted spanish military technology and used it against their enemies. they used rivers to transport their troops

The Inca war machine took great advantage from the development of an extensive system of paved stone roads and communication system they had as well as strategically storehouse’s locations.  

The answer is

A- They developed an extensive system of paved stone roads.

is this a multiple choice question? if so, could i see the answers to give you the right one!