Final answer:
Friedman and Rosenman concluded that Type A behavior, characterized by high stress and competitiveness, was significantly linked to an increased risk of heart disease compared to Type B behavior, which is more relaxed.
Step-by-step explanation:
Friedman and Rosenman conducted research that led to the identification of what is known as the Type A and Type B personality theory in relation to heart disease. They concluded that individuals displaying Type A behavior pattern — characterized by being workaholics, highly competitive, aggressive, and constantly rushing — were significantly more prone to heart disease compared to their Type B counterparts, who were more relaxed and easy-going. The study showed that heart disease was over seven times more common in Type As compared to Type Bs.