A 71-year-old female presents with the sudden onset of severe lower back pain. Physical examination reveals severe kyphosis, while an x-ray of her back reveals a compression fracture of a vertebral body in the lumbar area along with marked thinning of the bones. Serum calcium, phosphorus, alkaline phosphatase, and parathyroid hormone levels are all within normal limits. This woman’s bone changes are most likely due to
a. Osteopetrosis
b. Osteoporosis
c. Osteomalacia
d. Osteitis fibrosa cystica
e. Osteitis deformans