To be honest, since we live on Earth (assuming you do as well), Earth is the easiest planet to study. We don't know much about the other planets because we've never been to any of them. I believe that the second easiest planet to study is either Uranus or Saturn.
Is this a multiple choice question or...??
If not, I'd say, that its simple as scientists can easily decipher which variable caused the situations result. And thats because you may have one manipulated variable to be able to know the responding variable.
Animals or Organisms that live in extreme conditions like jellyfish with immense pressure at the bottom of the ocean. pls give brainliest homie