A catalyst speeds up a chemical reaction by A. decreasing the reaction enthalpy. B. providing an alternate reaction pathway. C. shifting the equilibrium. D. increasing the activation energy.

B. providing an alternate reaction pathway

Explanation:

For a reaction to occur, the molecules of the reaction must collide with a minimum energy called the activation energy. For this reason, every reaction has an energy barrier (activation energy) to be broken for the reaction to occur.

A catalyst can speed up a reaction by lowering the energy barrier(activation energy) and the reaction will follow an alternate pathway as a result of this.

However catalyst are unchanged chemically in reaction.

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).