I think it’s C. I know I’m right
Your Answer would be 3. Also known as Lithium.
Answer:
= 
Explanation:
Given that the woman’s maternal grandfather is color-blind, then it is possible that the woman is a carrier of color-blind allele.
Then probability that the woman is a carrier of color-blind allele is =
So if a carrier woman cross with a normal man
Let say the gene of the carrier woman is: 
and the normal man = 
so if we have a cross between
and
; we have:



we can see the offspring to be :
=normal unaffected female
= normal unaffected male
= carrier female for color-blind
= carrier male for color-bind
Then probability that of inheriting defective allele =
= 
Let's not forget that the probability that the woman is a carrier of color-blind allele is =
∴ the probability that the son is colorblind = 
= 
Answer: The human brain and other nerve tissues use mostly as fuel.