Which of the following is NOT a function of the skeletal system?

The skeletal system serves several critical functions, and among them, the production of hormones is not one of its primary roles. The skeletal system is primarily involved in mineral storage, such as calcium and phosphorus, which are essential for various bodily functions, including muscle contraction and nerve signaling. It is also responsible for blood cell production, occurring in the bone marrow, where red and white blood cells are formed. Furthermore, the skeletal system provides protection for vital organs, such as the heart and lungs, by encasing them within the ribcage and skull.

On the other hand, while bones do produce a hormone called osteocalcin, which is involved in regulating glucose levels and fat deposition, this function of hormone production is not significant compared to the more recognized roles of the skeletal system. Therefore, hormone production does not qualify as a primary function of the skeletal system, making it the correct response to the question.