Which of the Following Statements About Stable Hybrid Zones Is

Which of the following statements about stable hybrid zones is most accurate?

A) Stable hybrid zones rarely persist for more than 10-20 years.
B) Stable hybrid zones are most likely to be narrow because intermediate environmental conditions where hybrids are less fit than the parental species are likely to be narrow.
C) Stable hybrid zones are likely if strong pre-mating isolating mechanisms between the two species exist.
D) Stable hybrid zones are likely even if hybrids are selected against, if the hybrid zone is narrow and the parental species come in contact frequently.