Ans. is 'a' i.e., Blue sclera o Osteogenesis imperfecta, also known as brittle bone disease, is due to defective collagen type 1 synthesis.o It is inherited mostly as autosomal dominant but autosomal recessive pattern also seen in severe form. Clinical features of osteogenesis imperfecta# Blue sclera# Dentinogenesis imperfecta a Generalized osteoporosis# Osteoporosis given rise to bowing and multiple fractures. Fracture are usually due to trivial trauma but surprisingly heal well.# Other features: Deafness due to otosclerosis, joint laxity, dwarfism, broad skull, poorly calcified decidual teeth (Permanent teeth are normal).# Radiology shows wormian bones in the skull.