Answer:
a. genetic variations
Step-by-step explanation:
Genetic variation is the amount of differences in the DNA there is between individuals in a population. Generally, a high level of variation means the population is fitter, as they can more likely adapt to any changes.
Meiosis produces haploid gametes that fuse during fertilisation. These gametes can have any combination of alleles present in the individual, can undergo crossing over, and can fuse with any of the gametes in the other partner. These all provide opportunities for genetic variation and creating new combinations of alleles.