Im so sorry but your not putting enough details for me to answer your question
Answer: Genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).
By the end of meiosis, the resulting reproductive cells, or gametes, each have 23 genetically unique chromosomes. The overall process of meiosis produces four daughter cells from one single parent cell.
Explanation:
During meiosis, homologous chromosomes (1 from each parent) pair along their lengths. The chromosomes cross over at points called chiasma. At each chiasma, the chromosomes break and rejoin, trading some of their genes. This recombination results in genetic variation.
62 -- The roots absorb water for the plant, and also provide it with stability, ie to keep it from falling over.64 -- Structure B is a leaf, and a leaf's main function is to take in sunlight and perform photosynthesis, which makes food for the plant.
Meiosis takes place in the gonads of most organisms.
So the correct answer is A : Gonads.
Hope this helps :)
~Davinia.