Which of the following is an OTC emergency contraception brand?

Plan B One-Step is indeed an over-the-counter (OTC) emergency contraception brand. It is a single-dose pill that contains levonorgestrel, and it is designed to prevent pregnancy after unprotected intercourse or contraceptive failure. By being available OTC, it allows individuals to access it without a prescription, thus providing a timely option for preventing unintended pregnancies.

The other listed options, Noriday, Loestrin, and Yasmin, are not classified as emergency contraception. Instead, they are regular oral contraceptive pills used for ongoing birth control, but they are not intended for emergency use. Each of these brands contains a combination or a single hormone designed for daily use to prevent ovulation, regulate menstruation, and provide different health benefits, but they do not serve the purpose of emergency contraception like Plan B One-Step does.