Answer
(a) $HY$ is the stronger acid.
(b) $X^-$ is the stronger base.
(c) To the left.
Work Step by Step
(a) The solution that has the most quantity of $H_3O^+$ and $A^-$ is the one with the stronger acid, because it means that this acid dissociated in a larger scale.
(b) The solution with less $H_3O^+$ has the strongest conjugate base, therefore, "$X^-$" is the strongest base here.
(c) Since the strong electrolytes: "$HY$ and $X^-$", are on the right side, the reaction will proceed from the right to the left.
