I think the best answer is B. Even this is the broadest case for the Conservation of matter and the one for Energy, the only way this can be applied is in nuclear rxns.
Answer:
The correct answer is "Iron and oxygen act as Fe3+ and O2− ions respectively, forming rust (Fe₂O₃) in the presence of water by the formation of an ionic bond".
Explanation:
Rust is formed when iron reacts with oxygen in the presence of water (either if the iron is submerged or exposed to moisture in the air), forming the chemical compound Fe₂O₃. The presence of water is needed for rust formation because iron and oxygen act as ions when they are exposed to water, particularly Fe3+ and O2− ions respectively. The bond formed between these two elements are ionic bonds, because it is comprised of the reaction between a metal (iron) and a non-metal (oxygen).
D all of the above because it has all of them at the crust
There are two kinds of forces, or attractions, that operate in a molecule—intramolecularand intermolecular. Let's try to understand this difference through the following example.

Figure of towels sewn and Velcroed representing bonds between hydrogen and chlorine atoms
We have six towels—three are purple in color, labeled hydrogen and three are pink in color, labeled chlorine. We are given a sewing needle and black thread to sew one hydrogen towel to one chlorine towel. After sewing, we now have three pairs of towels: hydrogen sewed to chlorine. The next step is to attach these three pairs of towels to each other. For this we use Velcro as shown above.
So, the result of this exercise is that we have six towels attached to each other through thread and Velcro. Now if I ask you to pull this assembly from both ends, what do you think will happen? The Velcro junctions will fall apart while the sewed junctions will stay as is. The attachment created by Velcro is much weaker than the attachment created by the thread that we used to sew the pairs of towels together. A slight force applied to either end of the towels can easily bring apart the Velcro junctions without tearing apart the sewed junctions.
Exactly the same situation exists in molecules. Just imagine the towels to be real atoms, such as hydrogen and chlorine. These two atoms are bound to each other through a polar covalent bond—analogous to the thread. Each hydrogen chloride molecule in turn is bonded to the neighboring hydrogen chloride molecule through a dipole-dipole attraction—analogous to Velcro. We’ll talk about dipole-dipole interactions in detail a bit later. The polar covalent bond is much stronger in strength than the dipole-dipole interaction. The former is termed an intramolecular attraction while the latter is termed an intermolecular attraction.
