Which of These Have Researchers Found to Be a Consistent

Which of these have researchers found to be a consistent predictor of which adolescents will identify themselves as gay, lesbian, or bisexual later in life, as opposed to being exclusively heterosexual as an adult?

A) the adolescent's characterization of his or her parents as cold and distant
B) same-sex sexual encounters
C) same-sex attraction
D) Researchers have found no such predictor.