The correct answer is option B, 50%
Let us take the following case:
Genotype of heterozygous parent - (Aa)
Genotype of homozygous parent – (aa)
Allele I  - (Aa)
Allele II – (aa)
The cross between the two is shown below:
Aa  X aa
Aa, Aa, aa, aa
There are 50 % Aa, and 50 % aa allele.  
Thus, the allele I (Aa) is 50 %.  
 
        
             
        
        
        
Answer:
B it think
were did you get this question?
 
        
             
        
        
        
Answer:
the chloroplasts in the cells of the leaf
 
        
                    
             
        
        
        
Explanation: the movement of organelles and other substances within cells. Endoplasmic reticulum