Answer:
Explanation:
Nuclear does not leave a Carbon Footprint. The others are all made either hydrocarbons (natural gas and Petroleum) or carbon (coal).
 
        
             
        
        
        
Answer:
 the material that strengthens their cell walls
Explanation:
Chytrids originate from the kingdom fungi and a division known as Chytridiomycota. They contain a feature of unique characteristics by the presence of the chitin and the cellulose cell wall. The chitin made up the component of their cell wall in fungi but in Chytrids, the cellulose helps to strengthens their cell walls.
 
        
                    
             
        
        
        
Answer: Pia mater. The pia mater (Latin: tender mother) is a very delicate membrane. It is the meningeal envelope that firmly adheres to the surface of the brain and spinal cord, following all of the brain's contours 
Explanation:
 
        
             
        
        
        
Membrane of the cell/ cell wall and membrane if it is plant
        
                    
             
        
        
        
Answer:
The correct answer would be group D- 809 kg.
It can be explained with the help of pyramid of biomass.
Pyramid of biomass represents biomass or the amount of organic or living matter present at each trophic level in an ecosystem.
The amount of organic matter is usually expressed in grams per meter square (g/m²). 
There are usually four trophic levels in the pyramid of biomass: primary producers, primary consumers, secondary consumers, and tertiary consumers.
Usually, the biomass decreases as we go up the trophical levels specially in  terrestrial ecosystem. Inverted pyramid can be observed in case of aquatic ecosystem (biomass of phytoplanktons is less than that of herbivores). 
Here, maximum biomass (809 kg) belongs to the group D and hence, it would belong to primary producers.