What is the great "myth" that is commonly held in North America regarding the reason for the establishment of a taboo against first-cousin marriage in the United States?​

A) ​It is a religious prohibition and against biblical law.
B) ​It decreased the chances for the family to extend social alliances.
C) ​It would incite feuding within the nuclear family.
D) ​It would cause significantly increased numbers of birth defects.

First-Cousin Marriage

A type of marriage where the spouses are first cousins, sharing grandparents or having two of their four grandparents in common.

Myth

An old narrative, particularly one that deals with the origins of a nation or elucidates a phenomenon of nature or society, and commonly includes supernatural characters or happenings.

Birth Defects

Anomalies that are present at birth and can result in physical, intellectual, or developmental disabilities, varying widely in severity.