john is a farmer who wants to keep his soil as productive as possible. Which of these actions would help his achieve this goal?

Crop Rotation

Explanation:

When farmers plant pick their out seed they pick plants that compliment eacother

Example. farmers will plant corn one year and soybeans the next then corn again because corn puts the required mineralsin the soil for soybeans, and the soybeans put the needed minerals in the soil for corn to grow.

d. stage 4

explanation:

the existence of some kind of demographic transition is widely accepted in the social sciences because of the well-established historical correlation linking dropping fertility to social and economic development.[1] scholars debate whether industrialization and higher incomes lead to lower population, or whether lower populations lead to industrialization and higher incomes. scholars also debate to what extent various proposed and sometimes inter-related factors such as higher per capita income,lower mortality, old-age security, and rise of demand for human capital are involved.[2]

where is the picture? ?