I'd say B, because of the sanitation, but A might work toooooooo, bt id go with A.
Answer: B. Earth's present-day species evolved from older, identical species.
The evolution is the change or modification in the characteristics of a species over genration due to the process of adaptation and natural selection. The statement "Earth's present day species evolved from older, identical species is true about evolution". As, proposed by Darwin evolution is "descent with modification", which means that in a process of evolution species change and give rise to new species over generation. He proposed that newly evolved life forms can be traced back to their common ancestor.
Somatotropin
Somatotropin is a polypeptide growth hormone that regulates the growth of bone, muscle, and other body tissues. Somatotropin is secreted by somatotropic cells within the anterior lobe of the pituitary gland. Somatotropin is important in human development as it stimulates growth, cell regenerations and reproduction in humans and other animals. The levels of somatotrophin rise increasingly during childhood and also occur at its peak in puberty.
