You are presented with the question "What are highly probable in the evolution of a group of bipedal dinosaurs?" and the following answer choices: 
- group activities
 - heat energy
 - lack of teeth
 - animals
 - high altitidues
 - mammals
 - fur and fat
 - feathers

Now knowing that birds evolved from a group of bipedal dinosaurs called theropods and feathers are highly probable in the advanced bird-like theropods, choose the best answer.


 

        feathers 