Select the correct answer. How does adding oxygen (O2) to this reaction change the equilibrium?

2SO2(g) + O2(g) ⇌ 2SO3(g)

A.
The equilibrium shifts right to produce more SO3 molecules.
B.
The equilibrium shifts left to produce more O2 molecules.
C.
The equilibrium shifts right because of decreased collisions between SO2 and O2 molecules.
D.
The equilibrium shifts left with an increase in SO2 and O2 molecules.
E.
The equilibrium shifts left because of increased collisions between SO2 and O2 molecules.