A 51-year-old woman is diagnosed with primary osteoarthritis (OA) of the knee. The NP will educate the woman that which of the following could have contributed to or might worsen her OA?

Choice A reason: Diabetes mellitus may contribute to metabolic syndrome but is not a direct risk factor for primary OA. Choice B reason: Overuse and obesity are correct, but diabetes mellitus does not directly cause OA. Choice C reason: Overuse of joints, obesity, and aging are key risk factors for primary OA. Repeated mechanical stress accelerates cartilage degeneration, obesity increases joint load (especially in weight-bearing joints like the knee), and aging leads to cumulative wear and reduced cartilage repair capacity. Choice D reason: Congenital abnormalities cause secondary OA, not primary OA, which develops from chronic wear and tear.