Final answer:
Obesity is most commonly caused by a combination of excessive food intake, inadequate physical activity, and genetic susceptibility. Environmental factors, such as sedentary lifestyle and unhealthy food choices, contribute significantly to obesity.
Step-by-step explanation:
Obesity is most commonly caused by a combination of excessive food intake, inadequate physical activity, and genetic susceptibility. Environmental factors play a significant role in obesity, including a sedentary lifestyle and unhealthy food choices. Genetic factors also contribute to obesity, but they are not the sole cause. Obesity is not solely caused by psychological factors.