If we are talking about one single carbon atom, then 4 hydrogen atoms can be bonded to a carbon atom, because there is 4 electrons in the valence shell, and a valence shell needs 8 electrons in total, which causes the carbon to have 4 open bonds. A hydrogen has only one electron in its valence shell of 2, and needs one more to complete it. So, each hydrogen connects to 1 of 4 bonds on the carbon to complete the valence electron.
Fun fact, CH4 is methane.
        
                    
             
        
        
        
In the process of photosynthesis, the outcome or product is oxygen. In cellular respiration, oxygen is taken in to fuel the cells. Cellular respiration is the correct answer.
I hope this helps! 
        
             
        
        
        
The answer is B only because it makes wayyy more sense
        
             
        
        
        
Cyanobacteria were very simple organisms and performed were an role in changing Earth's early atmosphere. They carried out photosynthesis to produce the materials they needed to grow. In this process, they release Oxygen which is needed to sustain life on Earth for Humans and other organisms.
 
        
             
        
        
        
Step- by - step - explaination