If oxygen is removed, the amount of magnesium oxide

a.will increase
b.will decrease
c.will not change.
and why? Thanks for your help

If O2 is removed the reaction will shift to add more O2, which for a system at equilibrium, will shift to the left and that means less MgO. Doesn't that make sense. Removing O2 means we have less MgO formed in the first place.

I don't think this equation is a good one to illustrate Le Chatelier's Principle for at least two reasons.
a. Equilibrium is FAAAAR to the right.
b. Two solids (Mg and MgO) are involved and the concn of solids can't be increased after the first molecule of solid is present.