For a reaction system at equilibrium, LeChatelier's principle can be used to predict the "effect of a stress on the system".
<u>Option: C</u>
<u>Explanation:</u>
Le Chatelier's theory can be implemented to forecast a system's behavior due to variations in pressure, temperature, or concentration that will lead in predictable and contested variations in the system adjustments to establish a new state of equilibrium. This means that adding heat to a process would favor the endothermic path of a reaction, because this decreases the amount of heat generated in the system.
Here shift in equilibrium take place when volume increase, the total pressure decreases, which have potential to reverse the reaction, while on increasing pressure of system, the total volume decreases of the gaseous system, which can shift an equilibrium in the direction of the fewer molecules.