These changes can be natural, such as through variations in the solar cycle. 
<h3>Climate history</h3>
Clam shells 
2. 800,000 years ago
Ice cores
1. 150 million years ago
Oldest rocks in the world
5. 3.8 billion years ago
Tree cores
3. 10,000 years ago
Ocean sediments
4. 200 million years ago
With this information we can conclude that these changes may be natural, such as through variations in the solar cycle. But since 1800, human activities have been the main driver of climate change, mainly due to the burning of fossil fuels like coal, oil and gas.
Learn more about Climate in brainly.com/question/885982
 
        
             
        
        
        
I think it would be D hope this helps
        
             
        
        
        
Answer:
to maintain internal balance
Explanation:
 
        
             
        
        
        
 Cloning will not lead to designer babies because clones are a complete copy of the person being cloned. The clone would need to be genetically modified to be considered designer
        
             
        
        
        
The NH3 molecular geometry (molecular shape) is trigonal pyramidal. The NH3 bond angles are 107 degrees because the hydrogen atoms are repelled by the lone pair of electrons on the Nitrogen atom.