Final answer:
Afforestation is the correct term for planting trees on bare land prone to erosion; it establishes new forest areas, distinct from reforestation, which replenishes existing forests.
Step-by-step explanation:
Planting trees on a piece of land that is bare and prone to erosion is known as afforestation. This term describes the process of establishing a forest or stand of trees in an area where there was no forest cover before. It is different from reforestation, which refers to planting trees in areas that have been deforested, especially recently and is commonly used to counteract the effects of deforestation and soil erosion. Agroforestry systems integrate trees into crop farming systems for biodiversity conservation and can include complex systems or home-gardens. Silvopasture is the practice of combining forestry and grazing of domesticated animals in a mutually beneficial way. Hence, the correct answer to the question is afforestation (d).