The formula X + ZY → XZ + Y shows that O A. X and Y bonded into a more complex molecule.
O B. ZY has decomposed into two smaller compounds.
O C. X is a more reactive compound than Y.
O D. Y has changed into a new compound.

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).

it should have an internal chamber and two thermometers sticking out of the top. the internal chamber will also be closed off from the outside.