The correct answer is:
What would happen if love didn’t die?
An independent clause is a clause that can stand alone as a sentence. When you read the sentence "what would happen if love didn’t die? you could use it as a sentence by itself, doesn't need any complement to make sense. On the other hand, the sentence "If the poem is about going mad when love is lost," is the dependent clause, because it needs a complementary sentence to complete the idea. 
 
        
                    
             
        
        
        
Answer:
C. The water would become polluted. 
Explanation: 
Thames today is among one of the cleanest rivers across the globe and the question interrogates the impact of dumping wastes into it which would most likely be the pollution of water.<em> If people begin throwing the household waste into the river, it would lead to excessive water pollution again as it happened during 1830-60 when it became so polluted due to industrial and economic waste that it was affirmed to be dead biologically.</em> Around 10,000 people died due to water-borne disease Cholera as a consequence of the pollution of river Thames. Thus, if the people begin dumping again, it may lead to a situation worse than the previous spread of lethal diseases. 
 
        
                    
             
        
        
        
1. A
2. C
3. A
4.B
5.C
6.A
7.B
8.A
 Hope these are right:)