You are presented with the question "What feeds on plankton and nonliving organic matter?" and the following answer choices: 
- barnacles
 - mollusks
 - animals
 - the Sun
 - sharks
 - graptolites
 - bacteria
 - dogs

Now knowing that bivalves feed on plankton and nonliving organic matter and mussels are bivalve mollusks, choose the best answer.


 

  mollusks       