A school nurse is reinforcing teaching to a group of teenage clients about prevention of sexually transmitted infections (STIs). Which of the following practices is the most effective form of protection to include in the teaching?

A. The use of latex condoms: Consistent and correct use of latex condoms provides the most reliable barrier protection against the transmission of many STIs, including HIV, gonorrhea, and chlamydia. Condoms reduce direct contact with infected bodily fluids and mucous membranes, making them the most effective practical preventive measure for sexually active teens. B. Vaccination against vaccine-preventable STIs: Vaccines, such as HPV and hepatitis B vaccines, offer protection against specific STIs but do not prevent all infections. While important, vaccination alone cannot fully protect against STIs like gonorrhea, chlamydia, or herpes. C. Avoiding sexual contact if a partner is known to have an STI: Avoiding sexual contact with an infected partner reduces risk but is not always practical, as many individuals may be asymptomatic or unaware of their infection status. Reliance on this strategy alone may leave teens unprotected. D. Limiting sexual partners: Reducing the number of sexual partners lowers the overall risk of STI exposure, but it does not provide direct protection during sexual activity. Even with fewer partners, STIs can still be transmitted if barrier protection is not used.