You are presented with the question "what adults are barrel-shaped?" and the following answer choices: 
- offspring
 - fertile
 - barnacles
 - Length
 - insects
 - sea squirts
 - humans
 - beer

Now knowing that adult tunicates are barrel-shaped and tunicates, or sea squirts, are marine organisms covered with a gelatinous tunic, choose the best answer.


 

      sea squirts   