The correct option is D Very little growth in pot A but lot of growth in pots B and C.
Very little growth in pot A but a lot of growth in pots B and C is observed because pots B and C have a good amount of nutrients in their soil in the form of manure and fertilizers respectively. When turned into compost and fed to plants, cow dung becomes a nutrient-rich manure and also fertilizers like urea can enrich the soil with nitrogen.