Wolff's Law describes how the body responds by?

Wolff's Law is a fundamental principle in biomechanics which states that bone adapts to the loads under which it is placed. This means that when a bone is subjected to increased stress or load, it will remodel itself to become stronger and more capable of handling that stress. This remodeling often involves an increase in the bone's diameter to cope with the increased forces, thereby enhancing its structural integrity.

In contrast to the other choices, which address different aspects of musculoskeletal function, Wolff's Law specifically pertains to bone adaptation in response to mechanical stress. While regulating muscle fiber size, adjusting joint mobility, and strengthening tendons can occur with various forms of training, they do not directly relate to the primary focus of Wolff's Law on how bone reacts and remodels in response to the load it experiences.