A Magnetic Resonance Imaging (MRI)study Showed That Threat-Related Brain Structures

A magnetic resonance imaging (MRI) study showed that threat-related brain structures are deactivated when women hold their husbands' hands,and,in another study,relationship communication predicted how long people may survive after a diagnosis of congestive heart failure.Why were the two different studies contrasted in the text?

A) to show how men and women differ in relationships,with women focusing more on emotion in social relationships and men focusing more on the social hierarchy and stress
B) to show two different research methods-one focusing on biological measures and the other focusing on observational methods
C) to show two different research designs-one focusing on cross-sectional data collection and one focusing on longitudinal methods
D) to show two different kinds of reasons for studying relationships-one focusing on something special about relationships themselves (intrinsic reasons) and one focusing on the effects that relationships have on other important experiences (extrinsic reasons)