It would be B im pretty sure bro
It is one of the four layers that surround earth the other three are rock, water, air.
Scientists believe that at first these bears scavenged seal carcasses that had washed ashore, and gradually began to hunt the seals by waiting at the water's edge as the seals surfaced to breathe. This is believed to be an important step in the evolution of a new bear species, the polar bear
Over time the new polar bears were used to the cold climate and learnt how to fish, they then separated from the grizzly bears, they developed new creatures which would help them survive in one of the most dangerous climate.
Answer:
Grass-fed beef is the most sustainable choice. Grass-fed beef represents a net gain for the human food supply because cows eat grasses that we can’t eat (from land that is typically unsuitable for human crops) and turn it into beef that we can eat.
Explanation:
Cattle raised on a primarily foraged diet are termed grass-fed or pasture-raised; for example meat or milk may be called grass-fed beef or pasture-raised dairy. The term "pasture-raised" can lead to confusion with the term "free range", which does not describe exactly what the animals eat.
That said, grass-fed cows eat (mostly) grass, while grain-fed cows eat (mostly) an unnatural diet based on corn and soy during the latter part of their lives. To maximize growth, the cows are often given drugs, such as antibiotics and growth hormones.