Underground, at the point where slippage along the fault begins.
I would say A is the correct answer. B and C are definitely wrong, and I think D is talking about genes and not chromosomes.
Answer:
the brain stem
Explanation:
the structures of our brain stem, in conjunction with our spinal cord (not a part of our brain) is responsible for involuntary action. Not sure if it generate signals, but hey it's better than no answer.
For this information to be true, that would mean freckles is a dominant trait, and to not have freckles is a recessive trait. So that means if even someone's genotype has both the freckle and the no freckle gene, their phenotype will be freckles.