Which of the following complications is associated with prolonged immobility?

Prolonged immobility is known to lead to various complications, one of the most significant being deep vein thrombosis (DVT). DVT occurs when blood clots form in the deep veins, usually in the legs. The lack of movement inhibits proper blood flow, leading to increased blood viscosity and promoting clot formation. This is particularly a risk in individuals who are bedridden or who sit for extended periods, as the calf muscle pump that aids venous return is not utilized effectively, allowing for stagnation of blood in the veins.

In contrast, the other options suggest beneficial outcomes that are usually the result of regular movement and activity. Enhanced muscle flexibility, improved cardiovascular health, and stronger bones are typically associated with physical activity rather than immobility. Thus, DVT stands out as the primary complication directly linked to prolonged periods without movement, highlighting the importance of mobilization and preventative measures for individuals at risk.