Final answer:
The congenital abnormality characterized by a sac containing cerebrospinal fluid and spinal nerves protruding dorsally is myelomeningocele, a severe form of spina bifida that can lead to significant neurological symptoms.
Step-by-step explanation:
The condition described is called myelomeningocele, which is a type of spina bifida. Spina bifida results from a neural tube defect, where the neural tube does not close completely during fetal development. Myelomeningocele involves both the meninges and spinal nerves that protrude through an opening in the spinal column, forming a sac filled with cerebrospinal fluid. This leads to potentially severe neurological symptoms due to the involvement of the spinal nerves in the sac.
Whereas, meningocele involves the protrusion of the meninges without the spinal nerves and typically presents with fewer symptoms. Omphalocele and hydrocele are unrelated to the spinal cord. Omphalocele refers to the protrusion of internal organs through the belly button, while hydrocele is fluid buildup in the scrotum. Surgery may be required to correct myelomeningocele, ideally performed early to minimize neurological damage.
In summary, the correct option for the congenital abnormality characterized by the presence of cerebrospinal fluid and spinal nerves in a sac protruding dorsally is myelomeningocele, which is the most severe form of spina bifida associated with neurological complications.