Color? I'm going with color. Chem isn't my forte though
        
             
        
        
        
Answer:
A. They trap energy in the atmosphere.
Explanation:
Greenhouse gases are defined as gases that absorb and emit radiation within the infrared range. These gases allow the sun’s rays to pass through the ozone layer and warm the earth, but prevent this warmth from escaping atmosphere.
Greenhouse gases cause the greenhouse effect on planets. Examples of greenhouse gases in Earth's atmosphere are water vapor, carbon dioxide, methane, ozone etc.
 
        
             
        
        
        
Misunderstanding and fear of the criticism are two very common barriers of critical thinking.  
<u>Explanation:</u>
Critical thinking is defined as the type of thinking where a person goes beyond the normal day to day ideas of explaining a situation and thinks in a different way to solve out a problem. But this idea is very difficult for introverts. 
Misunderstanding is a very common problem in this field where the general population cannot think in a different way than what they are used to. And there’s a lot of criticism from a group of people who are there to criticize the new theory.  
 
        
             
        
        
        
C. Solvent
A solvent is a substance that can be dissolved. A solute is a substance dissolve in a solvent. Saturated is something where it holds as much of a substance as it can. Precipitate means it's evaporated.
Hope This Helped! Good Luck!