46) While walking down the street, a cat jumps out of an alley into the pathway of an adult. They note that his /her heart is "racing." this response is primarily due to:

The cell body of the first motor neuron that lies in the brain stem

Reflex circuitry produce by the ANS reflex

Parasympathetic effect on the vagus nerve

Secretion of the sympathetic neurotransmitters produce in the adrenal medulla