What change would shift the equilibrium system to the left? (3 points) A(g) + B(s) + Energy ⇌ 3C(g)

The question is incomplete; the complete question is;

What change would shift the equilibrium system to the left?

A(g) + B(s) + Energy ⇌ 3C(g)

Adding more of gas C to the system

Heating the system

Increasing the volume

Removing some of gas C from the system

Adding more of gas C to the system

Explanation:

When a constraint such as a change in concentration, pressure or volume is imposed on a reaction system in equilibrium, the system will adjust itself so as to annul the constraint.

Hence, the system has to shift its equilibrium position forward or backward as required in order to reestablish dynamic equilibrium in the reaction system.

In this case, as C is added, the equilibrium position moves towards the left hand side as desired.

"the periodic table is arranged in order of atomic number."