The answer would be C. A person who practices abstinence but drinks heavily would have the least risk of getting an STI. This type of disease is acquired by doing any type of unprotected sex with a person who has STI. The best way to prevent having this illness is to practice abstinence. And avoid any actions that might lead you to acquiring STI. People are at a higher risk of acquiring this if the a person has more than one sex partner, don't practice safe sex and sharing needles.
The person in the advertisement might be an actor, and she should be hesitant about the product. Always make sure you ask your doctor before using a product.