The answer to this question is A)5
These lines (there is four of them) are residuals of the fusion of the five sacrum vertebrae that are fused. These "vertebrae" or segments present a characteristics, being the first of them very similar to a lumbar vertebra, large, and the other vertebrae are<span> progressively smaller and flattened. They also present a curved shape being anteriorly concave.</span>
Molecular clocks use rates of mutation to measure evolutionary time.Mutations add up at a fairly constant rate in the DNA of species that evolved from a common ancestor. The more mutations that happened in each lineage, the greater is the differences between these lineages.
The answer is 5 hope this helps you have a great day
