How does overpopulation primarily pose a threat according to provided information?

Overpopulation poses a significant threat primarily through its direct impact on health outcomes, leading to increased death rates and child mortality. When a population exceeds the sustainable capacity of an environment, resources such as food, clean water, and healthcare become strained. This can result in malnutrition, insufficient medical care, and unsanitary living conditions, all of which contribute to higher mortality rates, particularly among vulnerable groups like children.

In areas experiencing overpopulation, healthcare systems may struggle to provide adequate services, which can exacerbate the situation. As more people compete for limited resources, the likelihood of disease outbreaks increases, and preventive care becomes less accessible, further heightening risks of mortality. Therefore, the link between overpopulation and increased mortality rates underscores why this option is viewed as a primary threat within the context provided.