Final answer:
A nuclear family is composed of one or two parents and their immediate offspring. It can include a married heterosexual or homosexual couple and their children. An extended family includes grandparents, parents, and children.
Step-by-step explanation:
A nuclear family is defined as a household composed of one or two parents and their immediate offspring. It is the smallest family structure and is often found in societies where geographic mobility is valued.
For example, in small-scale foraging societies and industrial/postindustrial societies, nuclear families are common. This includes situations where a married heterosexual couple and their young children make up the household, as well as situations where a married homosexual couple and their children form the nuclear family.
In contrast, an extended family includes relatives such as grandparents, parents, and children, while a nuclear family consists of parents and their children living in the same household.
Therefore, the correct answer is a) A married heterosexual couple and their young children.
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