Damien Is Cold-Shouldered by Most of His Colleagues as He

Damien is cold-shouldered by most of his colleagues as he was the only one in the team to be promoted. Adding to this, he recently lost a good friend in an accident. In the context of stress and depression, Damien is likely to develop depression if there is an ________.

A) activation of his body's emergency response system
B) increase in the amounts of serotonin in his brain
C) activation of his hypothalamic-pituitary-adrenal system
D) increase in the number of neurons in his hippocampus