Answer:
The answer is the 2nd picture: the coccyx bone in humans.
Explanation:
Vestigial Structure:
Structures or anatomical features that do not currently serve a function is the bodily processes of a living organism. Vestiges are believed to have performed active functions in the organism's ancestors throughout its evolutionary history. 
Coccyx Bone:
The coccyx or tailbone is an evolutionary remnant of our tree dwelling ancestors. Coccyx has no use in modern humans as we do not need to climb trees. 
The coccyx in modern humans serves as an anchor for muscles.
 
        
             
        
        
        
Answer:
I am pretty sure it would be A
 
        
             
        
        
        
Humans even though i dont believe in evolution but that is the scientific answer
        
                    
             
        
        
        
Answer:
The recombination frequency between two genes exhibits a positive correlation with the distance between them, that is, farther they are, and more will be the chance of recombination. Thus, recombination frequency is used to signify distance among the two genes, for example, 1 percent recombination frequency demonstrates distance of 1 map unit.  
Let us consider that the heterozygous female of genotype AaBb can generate four kinds of gametes, that is, AB, Ab, aB and ab. Of these, the two gametes are the outcomes of recombination, or it can be said that 50 percent are recombinants. Thus, it can be concluded that in case of two linked genes, the maximum probable recombination frequency is 50 percent.  
This shows that any genes, which are distant than 50 map units will function as unlinked and will function as if they were on distinct chromosomes, and the frequency of recombinant frequency will be 50 percent.  
In the given question, it is given that the map distance between the two genes is 80 map units, that is, more than 50 map units. The maximum probable recombinant offspring will be 50 percent of the entire offspring.  
 
        
             
        
        
        
The correct answer is <span>Ka = [H3O^+][HSO3^-]/[H2SO3] </span>