What does overpopulation tend to impact the most?

food quality
standard of living
medical advances
agricultural progress

Overpopulation most greatly impacts the STANDARD OF LIVING.

The answer to the question is actually contained within the word "overpopulation" itself. Overpopulation, as Biology Dictionary explains, "refers to a population which exceeds its sustainable size within a particular environment or habitat." In other words, within a particular region or society, overpopulation means that there won't be enough resources available within that region to supply everyone's needs adequately. So the standard of living inevitably will go down, and a greater number of people fall into poverty conditions.