Hint: There are many methods applied by farmers in agriculture that essentially helps to return nutrients to the soil without synthetic inputs. These methods additionally aim to interrupt the pest and disease cycles, and improve soil health, thus increasing the biodiversity on the farm.
Complete answer: Crop rotation is the practice of growing a series of various sorts of crops within the same area across a sequence of growing seasons. It reduces reliance on one set of nutrients, pest, and seasonal weed pressure, and therefore, enhances the probability of developing resistant pests and weeds.
Growing an equivalent crop within the same place for several years continuously gradually depletes the soil of certain nutrients and increases the adaptation as well as the growth of local weeds. Without balancing nutrient use and diversifying the pest and weed communities, the productivity of crops can become entirely dependent upon externally provided nutrients.
Conversely, neat crop rotation can reduce the necessity for synthetic fertilizers and herbicides by better using ecosystem services from various sets of crops.
So, the correct answer is option A. Crop rotation.
Note: Crop choice is usually associated with the goal, that the farmer targets a lot of aspects together at the same time like weed management, to increase the nitrogen availability within the soil, controlling for soil erosion, or in some cases to improve the soil structure and biomass. When discussing crop rotations, crops are classified in several ways, largely on what quality is being assessed.