Final answer:
The nuclear family is a small family structure consisting of one or two parents and their immediate offspring. It can take different forms, such as single-couple families and blended families.
Step-by-step explanation:
A nuclear family is composed of one or two parents and their immediate offspring, making it the smallest family structure. It is common in societies where geographic mobility is valued, such as small-scale foraging societies and industrial/postindustrial societies. Although the traditional nuclear family consisting of a two-parent household with one or more children has become less typical, it still exists in various forms.
One variation of the nuclear family is the single-couple family, which consists of one parent and their immediate offspring. This may occur due to divorce, death, or other circumstances.
Another variation is the blended family, which is the result of remarriage after divorce or the formation of a new relationship after the end of a previous one. In a blended family, parents have children from previous relationships, and they may also have children together.