The correct answer is A, WHEN THEY ARRIVED AT THE BEACH. 
In English language, an adverb is one of the part of speech. An adverb is a part of speech that talk more or qualifies a verb. It can also be used to qualify an adjective, another adverb or a clause. An adverbial dependent clause refers to an adverbial clause that can not stand alone. In the question given above, the statement given in option A is an adverbial clause, which quality the verb 'arrived'.
 
        
                    
             
        
        
        
Answer:
1. I  2. F 3. F  4. F   5. I   6. I   7. F
Explanation:
 
        
             
        
        
        
Answer:
Its a beneficial behavior to one's mental and physical health which is linked to a high level of self discipline and self-control.
Explanation:
 
        
                    
             
        
        
        
Answer:
d. Paul is protective of Mitchell.
Explanation:
got it right on edge :)
 
        
                    
             
        
        
        
Answer:true 
Explanation:
Natural arches commonly form where inland cliffs, coastal cliffs, fins or stacks are subject to erosion from the sea, rivers or weathering (subaerial processes). ... The alcoves erode further into the formation eventually meeting underneath the harder caprock layer, thus creating an arch.