Obesity creates a greater risk for dehydration in people because:

The correct answer highlights the nature of adipose (fat) tissue and its relationship with water content. Adipose cells indeed contain a lower percentage of water compared to lean tissue, which consists largely of muscle and other organs that have a high water composition. This water-repelling characteristic of fat means that individuals with higher levels of body fat, such as those who are obese, may have less total body water compared to their lean counterparts.

Understanding this physiological characteristic is crucial because it implies that a greater proportion of body weight in obese individuals is composed of fat, leading to a potential decrease in total body water. Consequently, this decreased water reserve can predispose these individuals to dehydration, especially if they do not maintain adequate fluid intake or if they lose water through activities such as sweating or urination.

While other factors such as metabolic rates, urine output, and hypothalamic function could also influence hydration status, they do not address the intrinsic relationship between body fat composition and water content in the same direct manner as the correct answer does.