Covalent Bonds hold together atoms within a molecule
        
                    
             
        
        
        
Answer:
C. Coral reef 
Explanation:
Coral reefs are both found in the littoral zone which is on the shore in a tidepool and in the benthic zone which is the low level of the ocean.
 
        
             
        
        
        
There isn't a responsible muscle because your back muscles calf and thigh muscles work together also to help get momentum you swing your arms up.<span />
        
                    
             
        
        
        
Inadequate dietary vitamin D or its deficiency leads to malabsorption of calcium. Nutritional disorder leads to the rare disease rickets, which causes bones to become soft and bend in children. In adults, vitamin D deficiency leads to osteomalacia, which causes weak bones, bone pain and muscle weakness. 
The body needs vitamin D to properly absorb calcium and phosphorus from the diet. However, keeping the right quantities of calcium and phosphorus in bones is challenging when vitamin D levels are low. 
The two sources of vitamin D are-
- Natural sunlight 
- Foods such as fish oil, Egg yolk and fatty fishes like salmon and mackerel
There are other disease conditions which lead to poor absorption of vitamin D-
- Inflammatory bowel disease
- Celiac diseases
- Kidney problems
To learn more about Rickets here-
brainly.com/question/26292489
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