How should an estate bequest (Wasiyyah) be distributed when specified for the categories of Zakat mentioned in the Quran?

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When a bequest is made to the categories of Zakat recipients mentioned in the Quran, those are the individuals entitled to receive the bequest. It is obligatory to allocate one-eighth of the bequest to each category, similar to a bequest made to eight tribes. The distinction from Zakat itself is that for Zakat, limiting distribution to a single category is permissible, whereas for a bequest, the intention is to specify who must receive the endowment. Distribution can be limited to a single individual within each category because including all members of the category is impossible.