Final answer:
2. Crop rotation is not a Bantu contribution to African agriculture.
Step-by-step explanation:
The correct answer is 2) Crop rotation. Crop rotation is not a Bantu contribution to African agriculture. Crop rotation involves planting a different type of crop in a field each year and then rotating to the next field the following year.
This practice helps to replenish soil nutrients and increase overall crop yields. On the other hand, terracing, irrigation, and slash and burn are all agricultural techniques that have been used by Bantu people in Africa.