The behavior in which an animal mates for life,lives with its mate,helps care for the young,and defends the family is _____ which is _____.

A) monogamy; common to species in which sexual dimorphism is strong
B) monogamy; common to species in which males and females resemble each other
C) polygamy; common to species in which males and females resemble each other
D) polygamy; common to species in which sexual dimorphism is strong
E) monogamy; common only to species of primates and species of larger nesting birds