A group of glands that affects specialized growth, development, sexual activities, and health of the body is which system?

The correct answer is the endocrine system. This system is fundamentally responsible for producing hormones that regulate a wide range of bodily functions, including growth, metabolism, sexual development, and overall health. The glands that make up the endocrine system, such as the pituitary, thyroid, adrenal glands, and pancreas, secrete hormones directly into the bloodstream. These hormones serve as chemical messengers that travel throughout the body, influencing various physiological processes and maintaining homeostasis.

In contrast, the muscular system primarily deals with movement and stability of the body through muscles. The nervous system is involved in transmitting signals between different parts of the body and is crucial for communication and coordination of activities. The immune system focuses on defending the body against pathogens and diseases. Each of these systems has distinct roles, but the endocrine system is uniquely equipped to handle the regulation and development of bodily functions through hormonal control.