Select the bone disorder in which bone resorption outpaces bone deposition, leaving the person with thin and often very fragile bones.

Choice A reason: Osteomalacia is a condition characterized by softening of the bones due to defective bone mineralization, often caused by vitamin D deficiency. While it leads to bone weakness and pain, it does not primarily involve an imbalance between bone resorption and deposition.

Choice B reason: Rickets is the pediatric counterpart of osteomalacia and results from inadequate vitamin D, calcium, or phosphate. It causes bone deformities due to poor mineralization but is not defined by excessive bone resorption.

Choice C reason: Osteoporosis is the correct answer. It is a systemic skeletal disorder marked by decreased bone mass and microarchitectural deterioration of bone tissue. The hallmark of osteoporosis is that bone resorption by osteoclasts exceeds bone formation by osteoblasts, leading to porous, fragile bones and increased fracture risk.

Choice D reason: Paget’s disease involves disorganized bone remodeling, with excessive bone resorption followed by abnormal bone formation. However, the newly formed bone is structurally unsound and enlarged, not necessarily thin or fragile in the same way as osteoporosis.