why Shi Huangdi ordered the construction of a massive road system built throughout ancient China?

it provided a way for his armies, as well as merchants and diplomats, to travel efficiently and quickly from the capital

it provided a way for his army to escape westward in the event of a Korean invasion of the North China Plain

it provided a way for only the royal family to travel safely from city to city in ancient China

it provided a way for foreign traders to enter the Chinese territory to bring much needed goods