Question

Is a type of genetic drift resulting from a reduction in population such that the surviving population is no longer genetically representative of the original population?

Answer 1

The answer is:  the "bottleneck effect" . 
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              The "bottleneck effect"   is a type of "genetic drift" resulting from a "reduction in the population"  such that the [surviving population]  is "no longer genetically representative" [of the original population] .
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