What is the process that allows mixing the combinations of genes in a single chromosome, resulting in a virtually infinite possible combination of genes?

Recombination during meiosis

Explanation:

The mixing of the combination of the genes is the cause of the variation and the genetic diversity on the Earth.

The mixing of genes takes place through the exchange of the gene segment which takes place during the gamete formation through meiosis in the sex cells.

The process which results in the formation of the combination of the genes is known as the recombination which colours during pachytene of meiosis I during which the crossing over between the chromosomes occurs. The exchange of alleles during the crossing over results in the production of a variety of traits and is the cause of biological diversity.

Thus, Recombination during meiosis is the correct answer.