Final answer:
The high rate of obesity in America is primarily due to lifestyle choices, influenced by excessive calorie intake and lack of physical activity, although genetics and environment also play a role. The Correct Answer is Option. D.
Step-by-step explanation:
The increasingly high rate of overweight and obesity among Americans is primarily due to lifestyle choices. While factors such as metabolism, heredity, and the environment play roles in influencing an individual's body weight, the primary reasons for the obesity epidemic are excessive food intake and inadequate physical activity. Socioeconomic status and the physical environment must also be considered, as they can affect the accessibility to healthy food options and opportunities for physical activity.
Furthermore, genetics can influence obesity, and certain individuals may be predisposed due to their genetic makeup. However, in an environment with sufficient food energy, the combination of high calorie intake and low physical activity is the most common cause of obesity. It's important to note that when both parents are obese, there's a higher likelihood of their offspring also being obese, underscoring the role of genetics.