Explain how farming techniques changes with the Bantu migration.

The correct answer is:

**c. The Bantu brought advanced iron tools and new crops such as cereal grains to the new regions they settled.**

### Explanation:

The Bantu migration, which occurred over several centuries and involved the movement of Bantu-speaking peoples across sub-Saharan Africa, significantly influenced agricultural practices in the regions they settled.

1. **Advanced Iron Tools**: The Bantu were skilled metalworkers who developed and utilized iron tools. These tools allowed them to clear land more efficiently for farming, as well as to cultivate and harvest crops more effectively than with previous methods such as those relying solely on stone tools.

2. **New Crops**: The Bantu migrations also introduced new agricultural practices, including the cultivation of crops that were well-suited to different climates, such as millet, sorghum, and later other staple crops. These innovations contributed to more stable food supplies and supported larger, more permanent settlements.

Overall, the changes in farming techniques due to the Bantu migrations had a long-lasting impact on the agricultural landscape and societal structures in the regions they settled.