A 75-year-old woman trips on the carpet in her home and falls to the floor. She immediately has marked pain in the right hip. On physical examination, there is shortening of the right leg and marked pain with any movement. A radiograph shows a right femoral neck fracture. The fracture is repaired. Six months later, a dual-energy x-ray absorptiometry (DEXA) scan of the patient's left hip and lumbar vertebrae shows a bone mineral density 2 standard deviations below the young adult reference range. Which of the following processes contributes most to development of these findings?
□ (A) Decreased osteoprotegrin production
□ (B) Decreased sensitivity of osteoblasts to dihydroxycholecalciferol
□ (C) Decreased secretion of interleukin-1, interleukin-6, and tumor necrosis factor-α by monocytes
□ (D) Increased sensitivity of bone to the effects of parathyroid hormone
□ (E) Mutation in the fibroblast growth factor receptor 3 gene
□ (F) Synthesis of chemically abnormal osteoid
