Question

the reactants are. choose one option. a the substances present when the reactions begins. b the substances present when the reaction is complete. c the properties that change after the reaction. d the energy that is released or stored during the reaction.

Explanation:

Answer:

The question seems incomplete as it doesn't clearly state what needs to be done with the options (e.g., which one is correct). However, based on the content, the discipline is Natural Science - Chemistry. If we assume we need to just list the options in the required format:
(A) the substances present when the reactions begin.
(B) the substances present when the reaction is complete.
(C) the properties that change after the reaction.
(D) the energy that is released or stored during the reaction.