I am pretty sure that the answer is B. extrusive rock. I hope that this helps you!! Good Luck!!
Actually, it could indeed be the independent variable.
One mole of oxygen gas, which has the formula O2, has a mass of 32 g and contains 6.02 X 1023 molecules of oxygen but 12.04 X 1023 (2 X 6.02 X 1023) atoms, because each molecule of oxygen contains two oxygen atoms.
Mass is calculated by using an objects inertia. Since inertia is a quality of matter that resists motion, we can apply an increasing force to an object until it accelerates.
Then, by measuring its acceleration we can now determine its mass using the simple equation F=m×a, except rewritten as m=Fa.
So we divide the force that we applied by the acceleration rate and we get the objects mass.
Without inertia this cannot be done.
∴ Answer is C
The answer is B) repel each other because you are gaining a positive charge and that is not a answer is leave repel each other.