Answer:
Cortisol, having many good friends calms the hypothalamus-pituitary-adrenal axis
Step-by-step explanation:
People with high social support show lower baseline levels of cortisol, which suggests that having many good friends calms the hypothalamus-pituitary-adrenal axis which is activated in fight and flight.
Cortisol is released via the activities of HPA axis to manage stress. The presence of good friends tends to reduce stress, hence a lower cortisol level in people who have good friends around them during periods of stress.