C as activation energy is the highest curve on the graph
        
             
        
        
        
Answer:
Magnesium, calcium, phosphorous, sulfur these are essential nutrients for plants. These are required in trace quantity but are very important for plant life. Point A. will be correct answer.
Explanation:
As in B. starch n cellulose are composed of only carbon, oxygen and hydrogen.
As in C. These elements are not required on special occasion but are necessary throughout plant life.
As in D.  C H N O  is the primary component plants need but these secondary nutrients are equally necessary for growth n structure of plant.
<u><em>So answer A. Is the correct option.</em></u>
Calcium plays the most important role in structure formation of plants. Also act as messenger molecule in signaling. Deficiency  of calcium caused wilting , weakened stem and ultimately death of plant.
Magnesium is the key element in chlorophyll molecule. It is necessary for chlorophyll formation.
Sulfur is another very important element in plant life, it is necessary for protein synthesis in plants.
Phosphorous plays an important role in  process of cell devision , photosynthesis and respiration.
Potassium is very crucial in gaseous exchange ,it operates the opening and closing of stomata. 
 
        
             
        
        
        
Answer:
C. Panthera leo
Explanation:
If they ask for the classification search on google what the animal. It tells you the name and classification. Ex-Peacock. Phylum: Chordata
Family: Phasianidae 
Ex-Lizard. Scientific name: Lacertilia
Class: Reptilia
Kingdom: Animalia
Phylum: Chordata
Order: Scaled reptiles
Rank: Suborder
 
        
                    
             
        
        
        
The answer would be, "C", "Plants". 
        
                    
             
        
        
        
Each of a Number of small areas of habitat, typically of one square meter, selected at random to act as samples for assessing the local distribution of plants or animals.