题目选项分析

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?

【选项】Only regular exercise is necessary to decrease cholesterol levels in the bloodstream of individuals of average weight.