Answer:
B an animal that can live in fresh water
 
        
                    
             
        
        
        
C- mushroom
Mushrooms break down (decompose) dead cells of animals and plants.
Algae, lichen, and oak trees go through photosynthesis and are producers.
        
                    
             
        
        
        
Answer:
Correct
Explanation:
Homeostatic is nothing but ability of a system or living organism to manipulate its internal environment to maintain a stable equilibrium, for example the ability of warm-blooded animals to ascertain a constant body temperature.
The Homoeostatic feedback mechanism has three basis components and they are independent to one another.
These components are receptor, effector and integrating center. The function of receptor is to sense external stimuli and send information to integrating center. The integrating center generally hypothalmus in brain sends this signal to effector for example an organ to react to the stimuli. 
So, the order  in a homeostatic feedback system stimulus, receoptor, control centre, effector is correct. 
 
        
             
        
        
        
Answer:
B. A small fraction of the energy is transferred to higher trophic levels, majority stays in the lower trophic levels
Explanation:
Energy transfer between trophic levels is insufficient. When an organism is eaten by another organism, not all of the biomass of prey forms the biomass of the predator. Majority of the energy is released into environment during cellular respiration. Some of the matter also remains undigested and is not used by the predator. Thus, only 10% of energy available at one level is transferred to the next level. So when we keep on moving up in a food chain, energy available keeps on decreasing.