Answer
The answer is choice a; $Mg^{2+}$ remains constant because of the large excess of $Mg$$F_2$, consequently, the solution would remain saturated even when the volume of solution is doubled.
Work Step by Step
The answer is choice a; $Mg^{2+}$ remains constant because of the large excess of $Mg$$F_2$, consequently, the solution would remain saturated even when the volume of solution is doubled.
