Which of the following is NOT a modifiable risk factor for obesity?

Family history is not a modifiable risk factor for obesity because it is determined by genetic inheritance and cannot be changed by individual actions or choices. Family history refers to the prevalence of obesity or related conditions within a person's biological family, which can influence one's susceptibility to gaining weight due to genetic predispositions.

In contrast, diet, stress, and inactivity are all behaviors and lifestyle choices that individuals can modify to reduce their risk of obesity. An unhealthy diet can be adjusted to include more nutritious foods and control portion sizes. Stress management techniques can be implemented to reduce stress-induced eating and promote healthier lifestyle habits. Lastly, increasing physical activity levels can combat inactivity, making it a changeable factor that can greatly impact weight management.