Answer:
d is the answer to this question 
 
        
             
        
        
        
Summary. Enzymes are catalysts that, within the mild conditions of temperature, pH, and pressure of the cells, carry out chemical reactions at amazing high rate. They are characterized by a remarkable efficiency and specificity. Substrates are the substances on which enzymes act.
        
                    
             
        
        
        
Answer:
Zebra mussels are spread from one body of water to another by natural flow, carried on the feathers or feet of birds, or by humans in bait buckets or on boats.
 
        
             
        
        
        
Answer and Explanation:
As I don't have access to live butterflies, the control group would be clay models that do not exhibit warning coloration, e.g. beige / white / brown. In contrast, the experimental group would be the clay models that exhibir a strong warning coloration such as color orange / red.
After preparing the clay 'prey', I would locate them in specific places outside where birds are able to detect them. Moreover, I would use a webcam to monitor the recurrence of birds in the area. 
1st experiment: Test whether birds approach the prey that exhibits both warning coloration (experimental group) and dull coloration (control group). Then, record the minutes they spent wandering near the prey.
2nd experiment: Test wheter birds feed on the prey that exhibits both warning coloration (experimental group) and dull coloration (control group). Record time.
Carry out statistical analyses.
Present results and discuss.