Concept:Planters are machines used for sowing seeds directly into the soil. A ridger is not a seed-planting machine but a tillage implement.Explanation:Broadcast crop planters, row crop planters, and grain drill planters are all types of seeding equipment used for planting crops.A ridger is a secondary tillage implement used after harrowing and before planting to make ridges or furrows.Its main function is land preparation, not seed placement.Therefore, it is not classified as a type of planter.Answer:D. Ridger planter