Answer:
The correct answer is - Adrenal gland.
Step-by-step explanation:
The HPA axis is a system that is used to show the representation of the interaction in to various body process to be maintain hypothalamus adrenal glands and pituitary gland.
It plays an important role in the stress response these system that regulates system including digestive system, sexuality, mood and other essential system.
Thus, the correct answer is - adrenal gland.