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

Verified Answer :

The answer is d. allowing the good genes to slowly spread through the population.

Natural selection is the differences in survival
and reproduction as the consequence of differences in genotypes and, consequently, phenotypes.  It is one of the factors of evolution that affects a frequency of different variations. 
In natural selection, genotype variations that
will increase the chance of survival and reproduction of some organism are
preserved and will be inherited Thus, "good genes" will be inherited. But, as the evolution, it will be slow process, since rarely evolution happens quickly.