An older client with osteoarthritis reports increasing pain and stiffness in the right knee and asks how to reduce these symptoms. In responding to the client, the nurse recognizes which pathology as the cause of the symptoms?

A. Loss of bone mineral density occurs in osteoporosis, not osteoarthritis. B. An infectious process in synovial fluid suggests septic arthritis, not osteoarthritis. C. Osteoarthritis is caused by wear-and-tear destruction of joint cartilage, leading to pain and stiffness. D. A systemic inflammatory response is characteristic of rheumatoid arthritis, not osteoarthritis.