Duvall's eight stages in the family life cycle of a traditional nuclear family have been used as ...

Duvall's eight stages in the family life cycle of a traditional nuclear family have been used as the foundation for contemporary models that describe the developmental processes and role expectations for different family types.
 
  Which of the following is an example of Stage IV of this family life cycle? 1. Families launching young adults (all children leave home)
  2. Families with preschool-age children (oldest child is between 2.5 and 6 years of age)
  3. Middle-aged parents (empty nest through retirement)
  4. Families with schoolchildren (oldest child is between 6 and 13 years of age)