Final answer:
Earthquakes were not a contributing factor to the collapse of the Old Kingdom, whereas crop failure, power struggles, and the cost of pyramid building were.
Step-by-step explanation:
The correct option : c
The Old Kingdom of Egypt faced several challenges leading to its downfall. Amongst these were issues such as crop failure due to environmental changes that rendered the land less fertile and disrupted the food supply. Power struggles also played a critical role as noble classes began to inherit power and land, thus weakening the central authority of the pharaohs. Additionally, the high cost of pyramid building contributed to economic strain as enormous resources were allocated to these monumental projects.
However, there is no evidence to suggest that an earthquake was a factor in the collapse of the Old Kingdom. Therefore, it can be concluded that while the Old Kingdom faced various social, economic, and environmental challenges, earthquakes were not among the reasons for its fall. The growth of the nobility and the economic diversification also played a role in the decline of royal authority. However, there is no historical evidence suggesting that an earthquake contributed to the collapse.