Which of the following is an essential step to prevent sexually transmitted infections (STIs)?
Avoiding multiple sexual partners and practicing safe sex (e.g., using condoms) are important preventive measures against STIs. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function.
