Answer: Echinococcus sp.
The most likely identification is E. granulosus, given the presence of a thick laminated membrane (2nd image) and abundant protoscoleces (images 1, 3, and 4). The best image for demonstrating the hooklets is the wet prep, in which the full outlines can be seen.
Since other forms of echinococcosis can also have thin laminated membranes, and less commonly, protoscoleces, so I would want to see the full histopathologic sections in order to confirm the diagnosis.
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