A16-year-old girl who has become sexually active asks the nurse, "what's the most effective way to prevent a pregnancy? " which method of preventing pregnancy should the nurse tell her is most effective?

The method of preventing pregnancy should the nurse tell the 16-year-old girl is most effective way to prevent pregnancy is abstaining from sexual intercourse. So the most effective way to prevent a pregnancy that the nurse tell the girl is Abstaining from sexual intercourse. 

Iwould say silver and gold