In Reference to the Clinical Research Studies Focusing on Factors

In reference to the clinical research studies focusing on factors that are implicated in heart disease, which of the following is an accurate statement?

A) Males who displayed a type A behaviour pattern were less likely to develop coronary heart disease than females in the type A group.
B) Younger males in the type A group were much less likely to develop coronary heart disease than older males in the type A group.
C) Both men and women with the type A behavioural pattern were twice as likely to develop coronary heart disease than were non-type A individuals.
D) In comparison to 'white collar' workers, men in lower socioeconomic positions were more likely to develop coronary heart disease.