Final answer:
Erosion of hillsides became a significant issue for the Maya primarily due to deforestation and intensive agricultural practices that removed vegetation cover, making the soil prone to erosion, eventually contributing to environmental degradation and societal challenges.
Step-by-step explanation:
Erosion of hillside became a significant problem for the Maya due to deforestation and intensive agricultural practices. The Maya civilization expanded agricultural production to meet the needs of their growing population. This expansion led to extensive deforestation, which in turn caused a loss of vegetative cover that would usually protect the soil from the erosional impacts of rain. With the removal of trees, the soil was more susceptible to being washed away, thus contributing to soil erosion. Large-scale deforestation also doubled the amount of sediment discharged into the oceans, further indicating the intensity of the issue.
Moreover, without forest cover, erosion rates escalated, leading to a substantial amount of soil erosion. As indicated by historical studies, the Maya faced environmental challenges, including soil erosion, which put pressure on their society and may have contributed to the decline of their civilization around 900 CE. Environmental degradation not only impacted their agricultural stability but also possibly played a role in the internal disorder and uprisings that arose within their civilization during their period of decline.
Therefore, the correct answer to why erosion of hillsides became such a problem for the Maya is B) Deforestation and agricultural practices contributed to erosion.