Which of the following statements about grey matter is true?

The possible answers are : 
A. it makes up the outer layer of the brain 
B. it's composed of an axon. 
C. it transmits nerve signals from one area of the CNS to another. 
D. it's composed of dendrites

The correct answers are A and D

The gray matter of the brain is made out of nerve cell bodies, dendrites, and unmyelinated axons. The outer layer of the brain's cortex is made out of the gray matter and the inner layers are made out of white matter.
The white matter is made out of myelinated axons that transmit nerve signals throughout the nervous system. The white matter is white because the myelin that surrounds the axons is white.

Giga is the second highest prefix on the normal scale, the first is terra.

Active site is where they touch.