The answer is letter A.
Developing poise under pressure and self-esteem affects the overall health and wellness of a person's mental health. Mental health refers to a person's psychological and emotional well-being. When a person is confident about his/her stature mentally, he/she will have the capacity to withstand different kinds of stress and make constant and wise decisions at all times.
Mental health is mostly a mental image you have of yourself and how you think the world views you. Developing a strong mental health is a sure path to wellness.