Final answer:
The guards behind Moctezuma suggest the importance of protection and security in the Aztec Empire.
Step-by-step explanation:
The three guards behind Moctezuma suggest the importance of protection and security in the Aztec Empire. Moctezuma refers to the kings who came before him as representatives who guarded and preserved the Empire for future rulers. This implies that the guards behind Moctezuma were responsible for maintaining the safety and stability of the empire. The presence of guards and sentries at important gateways and the emphasis on protecting the people and the sacred figures further highlights the significance of security measures in the Aztec civilization.