The answer is - Ocean.
All of the oceans in the world are connected, so they practically represent one huge body of water, which is by far the biggest in the planet, and is also a body of water that consist salt, thus it has salty water.
The oceans have sub-divisions, smaller than them, called seas. They range a lot in size, while some are huge, others are smaller than some big lakes. They represent a remote, peripheral part of the oceans, naturally surrounded by some geographical land forms, still they are part of the oceans.
The maximum number of orbits in an atom is seven.
So the answer is C) Seven (7).
Bad gases in the air, like the smoke from cars. the trees filter that.
The name of the island is honshu