Final answer:
The changes in the US population today include a decline in marriage rates, a rise in cohabitation, and a shift in family structure towards more diverse forms such as single-parent and extended family households. The most accurate statement is that nearly half of all American children are born to unmarried mothers.
Step-by-step explanation:
Which of the following describes the changes in the US population today? In examining the transformations within the U.S. demographic landscape, several trends are evident. Firstly, there has been a significant decline in marriage rates since the mid-20th century, with households headed by married couples dropping from 66 percent in 1960 to 45 percent by 2010. This demonstrates a shift in the social structure where the prevalence of married households is no longer a majority.
Additionally, cohabitation has become increasingly common, with nearly half of heterosexual women aged fifteen to forty-four reporting that their first shared living situation was with a partner to whom they were not married. The growth of unmarried cohabitating couples reflects changing attitudes towards marriage and family structures in the United States.
Furthermore, the configuration of American families has diversified. While still prominent, the traditional model of a nuclear family is being supplemented by a rise in single-parent households, same-sex couples, and extended families living together. This ideational change signifies a broadening perspective on what constitutes a family in contemporary society.
Therefore, the statement that closely aligns with these observations is 'C. Almost half of all American children today are born to an unmarried mother,' reflecting both the rise in unmarried cohabitation and the changing notions of family and marital status.