While Studying Possible Factors Related to Heart Disease, Two Cardiologists

Multiple Choice

While studying possible factors related to heart disease, two cardiologists, Meyer Freidman and Ray Rosenman, noticed that there were discernible differences in behavioral patterns between men who were and were not prone to coronary problems. This observation led to the identification of Type A and Type B personality types. The source of Friedman and Rosenman's initial research idea can best be described as

A) the use of metaphors.
B) serendipity.
C) resolution of conflicting ideas.
D) improvement on old ideas.