Answer:
RADON GAS
Explanation:
Radon is a naturally occurring gas, which is produced due to the radioactive decay of the Radium element. It is one of the dense gas that is mostly concentrated in the lower portion of the houses, and are trapped in the cracks and fractures of the walls of houses and buildings.
Radon gas is an invisible, colorless and odorless gas, which is a very harmful gas, and exposure to Radon gas can cause an individual to suffer from cancer.
In recent studies, it has been found that in many parts of North America, a large number of residents are exposed to Radon gas, which led to an increased risk of cancer.
 
        
             
        
        
        
A is the Stigma and B is the Style
The stigma is part of a pistil Where pollen germinates and it provides receptacle pollen
The style is is where pollen deposits
        
             
        
        
        
An organisms role is important for the community because they help us to have food & to keep us alive