How many alleles for each trait does an individual inherit from their parents?

An individual inherits two alleles for each trait, one from each parent. This diploid condition is characteristic of most sexually reproducing organisms. During reproduction, each parent contributes one allele to their offspring, which combine to form the genotype of the child. This is foundational in understanding Mendelian genetics, where traits are often determined by two alleles that can be either identical (homozygous) or different (heterozygous). The presence of two alleles allows for the possibility of genetic variation, which is crucial for the process of natural selection and evolutionary adaptation.

Options indicating one, three, or four alleles do not reflect the typical genetic inheritance pattern observed in diploid organisms, which is why they are not correct in the context of this question.