Answer:
A noun clause that is functioning as the subject of the sentence Option C: 'Whoever travels the Pelly River' follows in the footsteps of the explorer Robert Campbell.
Explanation:
A sentence can have independent clauses and dependent clauses. Dependent clause is the noun clause of the sentence which can act as subject, object or complement of verb in a sentence. Noun clause is the dependent part of the sentence which functions as a noun. It is usually introduced in a sentence by the conjunction that.  It can also be introduced by other conjunctions like if, whether, whoever, who, where, when, what etc.
Option B and D noun clauses are acting as objects of the sentence. In Option D "Whoever travels the Pelly River" emphasizes the subject of the sentence. If we ask the question "Who follows in the footsteps", Answer is 'Whoever travels the Pelly River'. So, it is acting as the subject of the verb 'follows' in the sentence. 
 
        
             
        
        
        
Answer:
1. The best thing that happened to me recently was that i got a puppy! He's so cute. I love him!
2. My most treasured possession is my phone. My parents gave it to me for my birthday. They also got me 2 amazing hoodies. These objects make my world more meaningful.
3. I love taking care of animals. I volunteer at an animal shelter and I love helping out there. Dogs need love and care. My job is to feed them and take them out for walks to there happy!
4. My grandpa is one of the best people I know. Anytime I'm struggling with something or need some advice he's always there to help me. His food is also amazing and he taught me how to make really good oatmeal. He's nice, sweet, smart, and funny
 
        
             
        
        
        
C. Haiku is the most reasonable answer
        
                    
             
        
        
        
Well, people thought it was entertaining enough to go down in history. Heck, we're studying about it now.
        
             
        
        
        
Ulrichvon Gradwitz and Georg Znaeym