Answer:
The answer is C
Explanation:
The reason of this is because fortified means to protect something which leads you to the answer C
 
        
             
        
        
        
1. Even though
2. Despite 
3. Nevertheless
4. Whereas
5. Though
6. Still
7. In spite 
8. On the other hand
9. Whereas
10. Still
        
             
        
        
        
Answer: Maybe because Suddenly and deliberately attacked by naval and air forces
Looking toward the maintenance of peace in the Pacific
Useless to continue the existing diplomatic negotiations
A surprise offensive extending throughout the Pacific area
 
        
                    
             
        
        
        
The correct answer would be B, since complex sentences have 1 independent variable and one dependent variable.
The dependent variable would be: Everytime he hears a siren
Why? Because it is not a complete thought.
The independent variable would be: My dog howls loudly.
Why? This statement is a complete thought.
A would be a compound sentence
C would be a simple sentence
D would be compound complex.
Hope I could help!