Natural selection acts on variation by:
Aallowing the bad genes to quickly spread through the population
Callowing the bad genes to slowly spread through the population
Ballowing the good genes to slowly spread through the population
Dallowing the good genes to quickly spread through the population
Aallowing the bad genes to quickly spread through the population
Callowing the bad genes to slowly spread through the population
Ballowing the good genes to slowly spread through the population
Dallowing the good genes to quickly spread through the population