Answer:
3. Zebrafish
Explanation:
Molecular phylogeny is mainly based on the improvement of gene models for the reconstruction of genes. it also describes the gene trees and species trees. Each gene tree tells us about the history of species and information of those genes.
Here, a specific gene tree is mentioned which is similar to the Zebrafish. Out of five vertebrate lineages, the Zebrafish shows genetic evolution most rapidly. It also shows the longest branches.