GRE Logical Reading: ETS-GRE逻辑单题ETS - 11T54K8D5FTC35AQJ$

The argument above assumes which of the following? A. Many men who have never had heart disease have unusually low levels of testosterone. B. Having heart disease does not significantly lower the level of testosterone in men. C. Levels of hormones other than testosterone significantly affect the likelihood that a man will develop heart disease. D. Heart disease and lowered testosterone levels in men are the effects of a single common cause. E. High levels of testosterone have never been thought to contribute to a serious disease other than heart disease.