A 7 year old male presented to the local clinic experiencing mild, yet annoying, abdominal pain, diarrhea and nausea. Patient history revealed that the child lives in a shack where sanitation practices are marginal, at best. The dwelling is infested with rats and multiple insects. Stool was collected and submitted for parasitic study. Numerous suspicious forms, measuring 60 µm by 75 µm were seen. This child is most likely infected with:

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