RNA viruses can copy themselves which is harder for scientists to give an accurate conclusion to solve them.
        
             
        
        
        

Last option: Preserve an ecosystem

 • The establishment of a bird reservation is a way to preserve an ecosystem because reservation provides suitable environment to organism. A healthy ecosystem means large number of biodiversity.
 
        
             
        
        
        
Answer:
phytoplankton
Explanation:
Phytoplankton can be defined as a set of photosynthesizing microorganisms that live floating on the water surface. It is composed of microscopic algae and cyanobacteria, which can be unicellular, colonial or filamentous. These microorganisms are defined as the primary producers of an ocean grazing food network.
Because phytoplankton live in aquatic environments - both in limic (eg lakes) and marine environments - they have a number of adaptations that guarantee their survival in the water column.  Some of these microorganisms, for example, have flagella that aid locomotion; others, in turn, have gas vacuoles that aid in flotation, while some of them have mucilage, which surrounds the cells and ensures protection, flotation and locomotion.