(E) "describes a hypothesis about the sequence of events involved in the origins of a phenomenon, and then argues that those events occurred in a different sequence"
This is incorrect for two reasons: (1) The anthropologist in the passage points out that a different hypothesis is possible but does not actually argue in favor of this new hypothesis. This is made apparent through language like "that conclusion was unwarranted," "might have instead arisen," and "might then have led." (2) The first hypothesis presented by some researchers- that taboos originated for practical reasons- does not mention anything about symbolic, ritualistic reasons. Therefore, the two hypotheses have different components and go beyond merely reversing a sequence of the same events.
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