Answer:
Option C  
Explanation:
In simple words, Gallup poll and Harris poll are two private organisation involved in conducting opinion polls for general public. Both of these companies are America based.
These companies collect and analyze different kinds of data and are popular for their honest and diligent work ethics. These organisations have been very helpful to the state as well as other private entities. They conduct their polls worldwide. 
 
        
                    
             
        
        
        
An indefinite pronoun is a pronoun that doesn't refer to a person or thing in particular so i'm going to say C. each
        
                    
             
        
        
        
Because the author has researched the area and talked to people who know the land
        
             
        
        
        
Answer:
a. Run on
Explanation:
'The Canadian side of Niagra Falls is beautiful,' is a complete thought, therefore it should be followed with a period.