Final answer:
Shi Huang-di developed The Great Wall of China as a security measure to protect against northern invasions. It was a massive construction effort that involved extensive labor and was part of an overall defensive strategy that defined Chinese statecraft for centuries.
Step-by-step explanation:
Famous Security Measure Developed by Shi Huang-di
The famous security measure that Shi Huang-di developed was A) The Great Wall of China. This immense fortification was constructed to protect the Chinese empire against invasions from the north, specifically from nomadic tribes. Although parts of it predate his reign, Shi Huang-di significantly extended and fortified these walls, employing hundreds of thousands of workers in the process. Alongside the physical construction, entire systems for communication and logistics were developed, including garrisons, roads, beacon stations, and couriers, enhancing the overall defensive capabilities of the Great Wall.
While later dynasties, such as the Mings, continued to improve and extend the wall, it originated under the Qin dynasty and Shi Huang-di's militaristic expansion. This structure symbolized a defensive strategy that has been a key element of Chinese statecraft throughout history. Moreover, the construction of the Great Wall and the Terracotta Army, another grand project from Shi Huang-di's reign, required substantial labor, which was both a form of taxation and a legal obligation under the Qin's codes.