In some societies, closely related members of the ruling class and the upper class marry to preserve their power and wealth within their families. this is a practice known as question 4 options:

The practice being described above is endogamy. This is defined as a way of having to marry an individual that is of the same group of the partner or a specific social group in which the person from a different culture or group is considered to be unsuitable by means of continuing the culture of their ancestors or because of certain reasons.

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