DNA is transcribed to RNA, which is translated into proteins. So DNA is in charge of making proteins (this narrows it down to either A or D). When there is a change in a person's genetic information, it will not result in a contagious disease. Those are usually caused by bacteria or viruses. A change in DNA could potentially result in a genetic disease. Therefore, answer A is correct. Hope this helps! :)
I think it’s b because it is talking about iceman body
A cow eats plant material like hay and grass that is full of cellulose. Cellulose is very hard to digest, so the cow relies on bacteria and other organisms that live inside them to break down the cellulose into a form from which they can extract nutrients. The ruminant stomach is vastly different from your own digestive system. Without cellulose-digesting bacteria, cows wouldn't be.