Final answer:
A diploid individual possesses two alleles at a specific locus. While populations may have multiple alleles for a gene, each diploid organism can only carry two alleles at each gene locus. These two alleles can be the same or different versions of the gene. The correct option is c.
Step-by-step explanation:
The number of alleles a diploid individual possesses at a specific locus is two.
In the context of genetics, a diploid organism, such as a human, has two sets of chromosomes – one inherited from each parent. This means that for any given gene, a diploid organism carries two genetic copies. These copies, known as alleles, might be the same (homozygous) or different (heterozygous) in the individual.
For example, one individual may have an allele for white flower color and another allele for violet flower color on homologous chromosomes. It's important to distinguish between individual and population genetics. While an individual can only have up to two alleles at a specific gene locus, there are often many more than two alleles present within the gene pool of a population.
Despite this diversity, each member of a diploid species only carries two of those alleles at any single locus. Mendel's studies of genetics implied a simpler two-allele system, but natural populations can exhibit multiple alleles controlling a single characteristic.
Therefore, the correct option is c.