Final answer:
The percentage of breadwinner-father/stay-at-home mother families in the US is most likely 'A. 10%' considering the significant shift in family structures and the decline in traditional nuclear families with married parents.
Step-by-step explanation:
Number of Breadwinner-Father/Stay-at-Home-Mother Families
When exploring the structure of families in the United States, data has shown significant changes in the composition of household types over the years. In the context of breadwinner-father and stay-at-home-mother families, we look at the traditional nuclear family structure, which has been on a decline.
According to the 2010 census, 66 percent of children under seventeen years old were living in households with two married parents, a decrease from 77 percent in 1980. While this number suggests that a majority of children still live in two-parent households, it does not exclusively represent the breadwinner-father, stay-at-home-mother dynamic.
With the rise of single-parent households and variations of nuclear families where parents are cohabiting but not married, and considering that only 66 percent of children live with two married parents, the number that most closely reflects breadwinner-father/stay-at-home mother families in the U.S. is considerably lower than the options provided.
As such, the answer to what percentage of families are comprised of a breadwinner-father and a stay-at-home mother is most likely 'A. 10%'. This reflects the significant social changes and increased diversity in family structures over time, including single-parent families and homes where both parents work.