The right answer is True.
If the selection is made on the phenotype, at the individual level, the understanding of the variation of the characters over time and thus of the evolutionary processes requires that one is interested on a larger scale: sets of individuals ( populations).
The genetic diversity resulting from mutations and rearrangements of the genome means that at a given moment, a natural population is not homogenous from a genetic point of view: there are for the most part genes and sequences several alleles, whose frequencies ( allelic frequencies) will vary over time (it could increase, and sometimes decreaqse geneic diversity between the individuals).
