Which of these sentences from the section "Uncovering New Complexities" BEST develops a central idea of the article?
(A) For one thing, she was still using her birth name and still preferred being referred to as "she."
(B) And while other trans kids often talk about how they've always known they were born in the "wrong"
body, she said, "I just think I need to make alterations in the body I have, to make it feel like the body I
need it to be."
(C) Many of us learned in high school biology that sex chromosomes determine a baby's sex: XX means it's
a girl, XY means it's a boy.
(D) It's possible to be XX and mostly male in body and mind, just as it's possible to be XY and mostly
female.