B. Fertilizer is any substance used to add nutrients to the soil to
promote soil fertility and increase plant growth. Notice how
nothing in there mentions the actual soil health; that's because not
all fertilizers are made the same and not all are healthy for the soil
health relies on a balance of macronutrients and micronutrients,
as well as microbial health. It's vastly more complicated than
simply adding nitrogen, phosphorus and potassium (NPK) to the
ground and calling it a day.