The correct answer is: B. check flooding.
Check flooding is a method of irrigation that is used on rolling land. It involves creating small dams or checks in the furrows to create pools of water. The water then seeps into the soil and irrigates the crops.
Border flooding is a method of irrigation that is used on flat land. It involves creating a raised border around a field and then flooding the field with water. The water then flows over the border and irrigates the crops.
Furrow flooding is a method of irrigation that is used on both flat and rolling land. It involves creating furrows in the soil and then flooding the furrows with water. The water then flows along the furrows and irrigates the crops.
Free flooding is a method of irrigation that is used on flat land. It involves flooding the entire field with water. The water then flows over the surface of the soil and irrigates the crops.
Check flooding is the best method of irrigation to use on rolling land because it allows the water to be applied evenly to the crops. The other methods of irrigation, such as border flooding, furrow flooding, and free flooding, are not as effective on rolling land because the water is not applied evenly.