Jocelyn Is Two and a Half Years Old

Jocelyn is two and a half years old. What can be expected of her knowledge regarding sexual identity?

A) She knows that babies dressed in yellow can be either boys or girls.
B) She knows that she will grow up to be a woman like her mother.
C) She is knows she is a girl, but she's not sure about the sex of her brother.
D) She knows she is a girl and her brother is a boy.