The Lack of Cross-Gender Interaction in the Middle Childhood Years

The lack of cross-gender interaction in the middle childhood years means that

A) girls and boys may not learn to like each other and have difficulty making cross-gender friendships.
B) boys' and girls' friendships are restricted to members of their own sex.
C) girls and boys do not have enough time or opportunity to learn about each other's differences and/or similarities.
D) it is more difficult for boys and girls to build social competence.