Answer:
The correct answer is A) Biochemical test
Explanation:
In microbiology biochemical test is used to examine the metabolic activities performed by bacteria to identify that microorganism. So in biochemical test enzymatic reaction of cell is usually investigated because there is difference in enzymatic activity of different species of bacteria.
For example, catalase test that is used to differentiate between catalase-positive and catalase-negative bacteria is an example of biochemical test. Catalase-positive bacteria have the catalase enzyme that breaks hydrogen peroxide into water and oxygen which is confirmed by bubbles that appear on glass slide.
Catalase negative bacteria do not form bubbles when they are put in hydrogen peroxide which shows that they lack catalase enzyme. So the right answer is A.
 
        
             
        
        
        
Answer:
mutualism
Explanation:
It's a symbiotic relationship beneficial to both symbionts. 
in this case E. Coli helps with the absorption of Vitamin K and other important vitamins for the human body in the colon. While, Human (host) provides shelter for it
 
        
             
        
        
        
The answer is C plants do photosynthesis to make their own food however animals do not
        
             
        
        
        
C. <span>When water in a lake freezes, it floats, providing insulation for organisms below.
This </span> best describes an effect of the low density of frozen water in a lake.
        
                    
             
        
        
        
The climate that has slown down soil formation is TEXAS. california is not low on soil since they grow oranges. so yeah thats the answer