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Re: It’s worth wondering if the increase in diagnoses of
[#permalink]
14 Oct 2017, 15:46
Explanation
The word once here signals a change in the direction of meaning. As the sentence ends with the idea that the behaviors in question were once “considered fairly normal,” you need something for the blank that means “uncommon.”
Mythical and fabulous may seem to fit, but they’re too extreme. Anomalous and aberrant work much better.
Hence options anomalous, aberrant are best fit!