<u>Answer</u>: The answers are matched as follows:
African forests have been hunted to near extinction levels to obtain ivory-------------->human exploitation
The eruption of mount Saint Helens destroyed some populations of conifers------> natural disasters
An infection with a fungus reduced the population of North American Elm trees ----> disease
Increasing global temperatures have altered migration patterns of humpback whales ------>climate change
<u>Explanation</u>:
- <em>Human</em> <em>exploitation</em> is the unethical or selfish use of resources to satisfy their own personal needs or for any profitable activity which harms the resources in such a way that they get limited. Humans have been hunting elephants to obtain ivory for many purposes such as making jewellery etc. and earning profits from it. Due to such extensive hunting they have driven the elephants to a level of extinction and thus, this is a form of human exploitation.
- Mount Saint Helens is a volcano and its eruption which harms the population of the trees in the area is a form of natural disaster since volcanic eruption is a <em>natural</em> <em>phenomena</em>.
- Fungal infection is a <em>disease</em> which is cause by the microorganisms which harms the population of the Elm trees.
- Increase of global temperature is a type of climate <em>change</em> and thus, this effect of alteration of migration pattern is caused by climate change.
 
        
             
        
        
        
By using the energy of sunlight, plants CAN convert carbon dioxide and water into carbohydrates and oxygen in a process called photosynthesis. 
Asphotosynthesis requires sunlight, this process only happens during the day
        
             
        
        
        
Central government.state government control
        
             
        
        
        
<span>from low concentration to high concentration</span>
        
                    
             
        
        
        
I do beleive that the answer is c