Both alleles are located on the same chromosome and present at the same place because genes come in pair. Each pair of gene is located at a specific place on a chromosome. If the two alleles present at a specific location are similar to each other, it is called homo-zygous while on the other hand, if both alleles are different from one another, they are considered as hetero-zygous.
The answer for the given question above about a cladogram showing the evolutionary relationships between different vertebrates is option A. <span> Amphibians and birds share a more recent common evolutionary ancestor than sharks and birds. I hope this helps.</span>
