Answer;
-23 in males
In humans, 23 in males is the only homologous chromosome pair that isn't the same.
Explanation;
-In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46.
-Twenty-two of these pairs, called autosomes, look the same in both males and females. The 23rd pair, the sex chromosomes, differ between males and females. Females have two copies of the X chromosome, while males have one X and one Y chromosome.
-The 22 autosomes are numbered by size. The other two chromosomes, X and Y, are the sex chromosomes.
All of the above points are valid for fossils' contributions in understanding the process of evolution. They allow us to study the ancestry, we can see the homologous organs or structures, if fossils are well-preserved; different fossils can lead us to follow the cycles of the changes that occurred during macroevolutions, and fossils can be used to study different populations which had different body structures for surviving in different environmental conditions.
Vestigial structures are considered evidence since scientists believe they are structures that were once used by a species ancestors but are no longer needed. They do not impair the organisms in any way, so there is no need for evolution to get rid of them. Vestigial structures are anatomical features that no longer seems to have a function or purpose in the current form of an organism of the given species. Examples are wisdom teeth, the muscles of the ear, the appendix, the tail bone among others in human.