X is connected to all the other parts of the body through the Y which contains thin,
thread-like tubes that run all around the body called Z.
Select the option which correctly identifies X, Y and Z.
| X | Y | Z | |
| A | Nerve | Brain | Spinal cord |
| B | Spinal cord | Brain | Skull |
| C | Brain | Spinal cord | Nerves |
| D | Spinal cord | Skull | Brain |
c