What is the role of hormones in the body?

Hormones play a crucial role in regulating various bodily functions, making option B the correct choice. They are chemical messengers released from glands into the bloodstream, where they travel to target organs and tissues to influence a range of physiological processes. This includes controlling metabolism, growth and development, mood, immune function, and the circadian rhythm, among others. Hormones help maintain homeostasis, which is the stable and balanced state of the body's internal environment.

While hormones may impact processes related to immune response or muscle mass, they primarily function through the dynamic regulation of these processes. Other options focus on specific outcomes or functions that hormonal regulation can influence but do not encompass the broader regulatory function that hormones serve in the body overall. Therefore, recognizing the diverse and pivotal role of hormones in coordinating and modulating a multitude of bodily functions is essential for understanding their significance in physiology.