Final answer:
The most common role of enslaved people in the Aztec empire was agricultural labor and farming, supporting the empire's economy by growing essential crops.
Step-by-step explanation:
According to the provided reading sections on the Aztec empire, the most common role of enslaved people was agricultural labor and farming. These individuals were often part of the lowest social tiers within Aztec society and were tasked with growing vital crops like maize, beans, squash, and chiles utilizing methods such as chinampas agriculture. Although human sacrifice and religious rituals were significant aspects of Aztec culture, the primary day-to-day role of slaves was to support the empire through agricultural labor and farming, which in turn fed the urban classes and reinforced the empire's economic foundation.