These questions are asking you to look at the coefficients of the balanced equations. A balanced equation will always give you mole ratios of one compound to another that can be used later on for other calculations.
So in this question we have 2 moles of H2O since the coefficient is 2 and we have 3 moles of O2 since there is a 3 for the coefficient.
So our mole ratio will be 2:3
What would the mole ratio be for carbon dioxide to oxygen?
Hope that helps!