Final answer:
The biggest consequence of decreased vegetative growth in the USA due to population growth is agricultural productivity decline, unsustainable resource use, and loss of biodiversity. Contributing factors include habitat destruction and the impact of climate change due to the excessive use of fossil fuels. Option B is correct.
Step-by-step explanation:
The biggest consequence of the reduction in vegetative growth due to population growth in the USA is agricultural productivity decline. As the human population increases, this leads to unsustainable resource use, habitat destruction, and negatively impacts biodiversity. Additionally, excessive use of fossil fuels contributes to climate change, which further exacerbates these issues. The term 'super harvest period' in the USA does not have a single, universally recognized definition, but can imply periods of exceptionally high agricultural yield, which are also affected by climatic and environmental conditions.
Population growth results in increased demand for natural resources such as wilderness areas, fresh water supplies, and fossil fuel reserves, leading to their depletion. Alongside, the atmospheric carbon dioxide levels rise, contributing to climate change and decimating biodiversity in the future. Therefore, to maintain environmental equilibrium and ensure sustainable development, it is imperative to address these challenges and adapt agricultural and conservation practices accordingly.