Assuming the options are:
the pons and the medulla.
the brain and the brain stem.
white and gray matter.
gray matter only.
The spinal cord is made up of white and gray matter.
Spinal cord is the part of the central nervous system, which connects a large part of the peripheral nervous system with the brain. It is a tubular structure extending from medulla oblongata ( in the brain stem) to the lumbar region (in the vertebral column).
