According to Research into Sexuality During Adolescence, Which of the Following

According to research into sexuality during adolescence, which of the following is true regarding teenagers and sex?

A) more girls than boys have had at least one sexual partner by the time they are in 12th grade
B) more girls than boys report that they have had more than four sexual partners by the time they reach 12^th grade
C) research has found that girls who get pregnant while still in high school are most likely to be either freshmen or sophomores when they become pregnant
D) the rate of sexually transmitted diseases in teenagers is much higher in girls than it is in boys