Answer:
The lamprey has the ability to latch on and ultimately weaken its prey.
Explanation:
A concise statement is one that is not too wordy but is rather straightforward and retains the original meaning intended by the author. When sentences are too wordy, the real meaning being conveyed could be lost. 
Concise statements are expressed in as few words are possible so as to retain the interest of the reader. This will also prevent the reader from skipping around in order to get the main point. With these in mind, the first option is the most concise statement.
 
        
                    
             
        
        
        
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.