I dont know how to do it other than just by trial and error.
First write out the equation and balance:
4X + 3O2 -> 2X2O3
So starting with aluminium, its Ar = 27
so moles of aluminium would be = 0.541 / 27 = 0.02mol
If it was aluminium then X2O3 is Al2O3 and the Mr = 27 x 2 + 16 x 3 = 102
Moles of Al2O3 would be = 0.79 / 102 = 0.0077
The ratio of X : X2O3 should be 2:1 (simplified from the balanced equation from earlier)
That means that if 0.02mol aluminium reacted then 0.04mol of the oxide should form, which it doesn’t so the answer isn’t A. Then just repeat that using the mass numbers from the periodic table for the other elements given and you’ll eventually (hopefully, unless I’m getting it wrong lol) find one that gives the right ratio. I dont know any other way of doing it but it’s multiple choice so maybe they want trial and error?