Which of the steps described in the item above (variation, selection,
and/or inheritance) are affected by the prior exposure of bed bug
populations to ddt? how are those steps or step affected?

variation

Explanation:

they adapt over time

The biological levels of organization of living things arranged from the simplest to most complex are: organelle, cells, tissues, organs, organ systems, organisms, populations, communities, ecosystem and biosphere

Explanation:

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