Which of the following is a characteristic of androgenic-anabolic steroids?

The correct answer highlights that androgenic-anabolic steroids are nearly identical to male sex hormones. These synthetic substances are designed to mimic the effects of testosterone, which is the primary male sex hormone. The term "androgenic" refers to the development of male characteristics, while "anabolic" pertains to the growth of muscle mass and strength. By closely resembling testosterone, these steroids can significantly influence muscle growth, recovery, and physical performance, which is a primary reason they are often abused in various sports and fitness contexts.

Understanding this characteristic is vital, as it frames the context of how steroid use may impact the body, particularly in relation to muscle development and other male traits. Other choices provided do not align with the core attributes of these substances: steroids do not enhance aerobic capacity in untrained athletes, do not decrease the rate of bone maturation (but rather may increase it), and are fundamentally different from female sex hormones in both structure and function. Therefore, recognizing the similarity to male hormones is essential for understanding the physiological effects of these substances.