A historian would most likely use the image in  <image 1> as support for which of the following? 
['Defensive walls were successful in preventing borderland nomads from conquering the Han dynasty.', 'The Han government built fortifications to protect the Silk Road.', 'Monumental architecture served both a religious and a military purpose in the Qin and Han dynasties.', 'Fortifications were built to project military power and defend against invasions.']