Final answer:
Birds and mammals are the groups of vertebrates that generally have the most species and are most abundant in tropical forests. Reptiles, on the other hand, have a lower number of species in tropical forests.
Step-by-step explanation:
In tropical forests, the group of vertebrates that generally has the most species is BIRDS. They are highly diverse and numerous in tropical forest habitats. For example, in the Neotropics, which includes parts of South and Central America, there is a high concentration of bird species.
Another group of vertebrates that is most abundant in tropical forests is MAMMALS. Although they may not have as many species as birds, mammals play important ecological roles in tropical forest ecosystems.
Reptiles, on the other hand, are not as diverse or abundant as birds and mammals in tropical forests. They typically have a lower number of species compared to other vertebrates.