Bypass surgery has been shown to be effective at helping extremely obese people lose weight. Some patients have lost as much as 300 pounds after undergoing the surgery, thereby substantially prolonging their lives. Despite the success of the treatment, most doctors have not embraced the surgery as a weight loss option.　 Which of the following statements, if true, best accounts for the lukewarm reaction of the medical community to gastric bypass surgery?

A.Gastric bypass surgery carries a high risk of serious complications, including death.

B.Obesity is one of the leading contributors to heart disease and hypertension, two leading causes of death.

C.Obesity rates among the American population have been increasing consistently for the last three decades.

D.Many patients report that losing weight through diets is ineffective, since they usually gain the weight back within six months.

E.Most health insurance plans will cover the cost of gastric bypass surgery for morbidly obese patients at high risk of heart disease.