Answer:
The correct answer would be more; closely related.
A transition refers to a point mutation in which a purine is converted into another purine (A↔G) or a pyrimidine is converted into another pyrimidine (T↔C).
In contrast, the transversion refers to a point mutation in which a purine is converted into pyrimidine or vice versa.
A transition is more common in nature as the conversion or exchange between similar nucleotide is easier as compared to the exchange between different types of nucleotide.
As they occur more frequently they would be more helpful in making phylogenetic trees between closely related organisms.