A neuron (also known as nerve cell) is an electrically excitable cell that takes up, processes and transmits information through electrical and chemical signals. It is one of the basic elements of the nervous system. In order that a human being can react to his environment, neurons transport stimuli.
 
        
             
        
        
        
pls mark as brainlist 
Explanation:
The law of substitution is also known as the law of equi-marginal utility or the law of maximum satisfaction. ... According to this law, if a consumer is to use all the available resource in the consumption of a single commodity then marginal utility,derived from every additional unit will decrease successively.
 
        
                    
             
        
        
        
Answer:
It is A
Explanation:
It is the only one that makes sense
Hope this helps
 
        
                    
             
        
        
        
<span>(According to Reference)
 
Whereas an onion epidermal cell has a cell wall, a human cheek cell does not. Instead, a semi-permeable membrane surrounds the cytoplasm of the cheek cell. While there are chloroplasts present in onion cells, they are absent in cheek cells.  </span>