Letter A is pointing to which structure or membrane?

 Name the Blue highlighted structure.

 What is the colored part called. Letter D

 Which nerve is this? Letter C.  Use the name not number.

 Together these 3 bones are known as the _______________.

How many pairs of sacral nerves are there?

 Name the crack the arrow is pointing to.

Name the blue highlighted structure. Hint: it is just superior to the foramen magnum.

Name the meninge that is closest to the spinal cord. Letter D.

Using the physiological type names, classify this neuron that the blue arrow is pointing to.