Out of the photosynthesis (plants).
        
                    
             
        
        
        
Answer:
The students are asked, how do the embryos provide evidence for organic evolution.
Explanation:
The embryos of different vertebrate groups have been found to have similar morphological features during the early stages of development. This similarity suggests a common ancestry. The closer the resemblance between the embryos in early stages the closer the phylogenetic relationship of the organisms.
 
        
             
        
        
        
Well considering birds follow humane rules, their selection and environment around them being thriving could effect their songs in a positive way. While a bird with a low selection of environmental stuff around them would effect their songs in a bad way giving off a more down manner.