Answer: The answer is C
Explanation: C and G pair with each other and T pairs with A and A pairs with U
 
        
             
        
        
        
The correct answer is letter (<span>C) The polar air mass moves south to replace the rising maritime tropical air mass.</span> These air masses are bringing cold air to warmer areas most especially during the winter and cool. These air masses are stable and usually does not form much cloud. While the Continental Polar air move down south, across the warmer land, the lower part of the air mass is modified and thus few clouds are formed.
        
             
        
        
        
D. Phytoplankton are most efficient 
 
        
             
        
        
        
Answer:
Gravitational forces.
Explanation:
The same reason the earth revolves around the sun, its all thanks to gravity!
-I hope this answers your question!
 
        
             
        
        
        
Answer:
What system interacts to perform the functions of regulation?
Body systems interact to perform the functions of regulation, nutrient absorption, reproduction, and defense from injury or illness