A Woman Had Unprotected Intercourse 36 Hours Ago and Is

A woman had unprotected intercourse 36 hours ago and is concerned that she may become pregnant because it is her "fertile" time. She asks the nurse about emergency contraception. The nurse tells her that:

A) It is too late; she needed to begin treatment within 24 hours after intercourse.
B) Preven, an emergency contraceptive method, is 98% effective at preventing pregnancy.
C) An over-the-counter antiemetic can be taken 1 hour before each contraceptive dose to prevent nausea and vomiting.
D) The most effective approach is to use a progestin-only preparation.