The correct options are
A Vertebrae
B Cerebrospinal fluid
D Meninges
The spinal cord is a long, fragile tubelike structure that begins at the end of the brain stem and continues down almost to the bottom of the spine. Like the brain, the spinal cord is covered by three layers of tissues called meninges and cerebrospinal fluid. In most adults, the spine is composed of 26 individual back bones or vertebrae. Just as the skull protects the brain, vertebrae protect the spinal cord.