<prompt> Bone in bone appearance is seen in-Active scurvyAMLOsteopetrosisOsteosarcoma  <response>: Ans. is c i.e., Osteopetrosis Bone within a bone is a descriptive term applied to bones that appear to have another bone within them. Bone within a bone appearance is seen in : - Normal neonate, Prostaglandin El therapy, Growth arrestrecovery lines n Heavy metal e.g., Lead poisoning, Bisphosphonate therapy, Hypothyroidism Hypoparathyroidism, Sickle cell anemia n Hypercalcemia Hypervitaminosis D, Osteopetrosis, Rickets Osteomalacia healed phase, Acromegaly, Scurvy healed phase. 