According to the passage, which body part is responsible for activating the fight-or-flight response?

a. heart

b. capillaries

c. hypothalamus

d. adrenal glands

The correct answer is D: the adrenal glands. More specifically, the adrenal medulla produces catecholamines, in particular especially norepinephrine and epinephrine. Estrogen, testosterone, cortisol, dopamine and serotonin also play a role in the response.

I believe it is the Hypothalamus. It activates the sympathetic nervous system and the adrenal-cortical systems. Fight or flight response is a specific biochemical reaction that both humans and animals experience during intense stress or fear. It is the body's response towards perceived threat or danger. During the reaction, certain hormones such as adrenaline and cortisol are released, thus speeding the heart rate, slowing digestion, and changing various other autonomic nervous functions, and therefore giving the body a burst of energy and strength.