Question

the natural age - related loss of bone mass is called osteomalacia osteogenesis imperfecta osteodysplasia osteopenia osteoporosis

Explanation:

Osteoporosis is a condition characterized by the natural age - related loss of bone mass, leading to increased bone fragility and a higher risk of fractures. Osteomalacia is a softening of the bones due to vitamin D deficiency. Osteogenesis imperfecta is a genetic disorder affecting collagen production in bones. Osteodysplasia refers to abnormal bone development. Osteopenia is a condition where bone density is lower than normal but not yet at the level of osteoporosis.

Answer:

osteoporosis