Which of the following statements is true regarding hemophilia?

Hemophilia is a genetic disorder that affects the body's ability to clot blood properly, which is essential for stopping bleeding. When someone has hemophilia, they lack certain clotting factors that are necessary for effective coagulation. This deficiency leads to prolonged bleeding, often with minor injuries or spontaneously without any obvious cause. Individuals with hemophilia may experience excessive bruising, bleeding into joints and muscles, and in severe cases, bleeding episodes can be life-threatening.

The other statements do not accurately describe hemophilia. Increased red blood cell count is not a characterizing feature of hemophilia; in fact, patients may have normal red blood cell levels but suffer from bleeding issues. Hemophilia does not lead to excessive clotting; rather, it results in inadequate clotting, which causes bleeding problems. Lastly, while hemophilia can lead to complications that may affect different parts of the body, it does not primarily affect respiratory function. Overall, the essence of hemophilia as a condition causing excessive bleeding is captured well in the statement that accurately reflects its clinical implications.