The answer is B <span>Endocrine system </span>
        
             
        
        
        
Answer: 
Carbon Dioxide 
Explanation:
Snails will produce only carbon dioxide, while the Elodea will produce carbon dioxide and oxygen gas. Snails and Elodea will produce more carbon dioxide, causing the water to turn yellow.
 
        
             
        
        
        
Once you have stopped for a school bus, do not pass until the driver signals you to proceed, the red lights stop flashing, or the bus starts moving ahead. Whenever a vehicle ahead of you stops to let  a pedestrian pass in front of you, you should stay in line and until the vehicle ahead proceeds.  
        
             
        
        
        
Answer:
O by building structures on natural habitat areas
Explanation:
The diversity within an ecosystem can be compromised by building structures on natural habitat areas. 
An ecosystem is part of the environment made up of living and non-living components in their natural habitats. 
- Diversity entails variations in the life forms within a particular ecosystem. 
- When human-induced pressure begins to impact the environment, diversity is threatened 
- Nature has its balancing effect the allow for a wide range of organisms to thrive. 
- When human builds structures, part of the natural habitat is lost.