Bo, While Riding Her Bicycle Down a City Street, Was

Bo, while riding her bicycle down a city street, was startled by the sudden sound of a car horn from directly behind. What did her hypothalamic - pituitary - adrenal axis do in response to the perceived stressor?

A) The hypothalamus communicated with the adrenal glands, which told the pituitary gland to release testosterone into the bloodstream.
B) The hypothalamus communicated with the pituitary gland, which told the adrenal glands to release cortisol into the bloodstream.
C) The hypothalamus communicated with the pituitary gland, which told the adrenal glands to release norepinephrine into the bloodstream.
D) The hypothalamus communicated with the adrenal glands, which told the pituitary gland to release adrenaline into the bloodstream.