Traits are inherited by genes on a chromosomes from the Mother and Father of the Offspring.They are passed down from our parents to us and there is 26 different chromosomes which determine what you look like.
The correct answer is HPA axis.
The Hypothalamic-Pituitary-Adrenal (HPA) axis is one of the most important neuroendocrine systems, which regulates the stress response and other functions such as the digestion, mood, emotions and the immune system.
The hypothalamus, when triggered by a possible stressor, releases two hormones; the vasopressin and the corticotropin-releasing hormone (CRH). CRH, in turn, triggers the release of the adrenocorticotropin hormone (ACTH) from the pituitary gland. As a result of the secretion of ACTH, cortisol is secreted by the adrenal cortex.
Cortisol is a steroid hormone, considered to be our body's stress hormone.