I am pretty sure that the atmosphere keeps the oxygen and light in it.
May be A is right up I think
Answer:
The more dense the rocks get
Explanation:
The deeper we go towards the center of the planet we will find more and more dense rocks. This is because of the force of gravity of the planet. That theory was devised by Sir Isaac Newton and it still holds true to this day. Every layer has more density than the previous layer all the way to the core.