Increases in the level of high-density lipoprotein (HDL)in the human bloodstream lower bloodstream cholesterol levels by increasing the body' s capacity to rid itself of excess cholesterol. Levels of HDL in the bloodstream of some individuals are significantly increased by a program of regular exercise and weight reduction. Which of the following can be correctly inferred from the statements above? ['A program of regular exercise and weight reduction lowers cholesterol levels in the bloodstream of some individuals.', 'Individuals who are underweight do not run any risk of developing high levels of cholesterol in the bloodstream.', 'Exercise and weight reduction are the most effective methods of lowering bloodstream cholesterol levels in humans.', 'Individuals who do not exercise regularly have a high risk of developing high levels of cholesterol in the bloodstream late in life.']