Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain
        
             
        
        
        
Option A is the right one for this question.
The undergrowth of tropical rainforest most likely requires less sunlight.
The tropical rainforest floor receives only 2% of the sunlight; only plants can grow in this region.
The forest floor is a relatively clear of vegetarian, because of the low sunlight penetration.
 
        
                    
             
        
        
        
Yes we have to maintain homeostasis so our bodies have to adapt to Mother Nature
        
             
        
        
        
Answer:
History of life provide evidence of technological advancement.
Explanation:
The study of history gives us a look into some of the planet's history and also how we came to know what we think about the universe. Such periods of exploration may seem uninteresting now, yet consider not having found them at all. Consider how we'd feel if we didn't have the information.
 
        
             
        
        
        
Answer: The cell membrane is selectively permeable.
Explanation: going thru last year notes