family the ultimate source of social inequality due to its role in transfer of power, property, privilege

The correct answer is Engels Perspective on the Family

The Origin of Family, Private Property and the State was written by Engels, from March to June 1884.

Engels seeks, based on Morgan's studies Iroquois, as well as identifying the moment in the evolutionary stage and the conditions that allowed the transformation of the monkey into man, characterize the kinship systems and forms of marriage that led to the formation of family, describing their phases, as well as the models created throughout the human development process. The invention of incest is the decisive step in the organization of the family itself, but as at this early stage the carnal relations were regulated by a tolerant trade-tolerant promiscuity between parents and children and between people of different generations, with no also the prohibitions and barriers imposed by culture, nor relations of marriage or descent organized according to kinship systems culturally defined, it is not possible to speak of family in this period.