Consider two Group IV metal ions X²⁺$X^{2+}$ and Y²⁺$Y^{2+}$. A solution containing 0.01 M X²⁺$0.01 \text{ M } X^{2+}$ and 0.01 M Y²⁺$0.01 \text{ M } Y^{2+}$ is saturated with H₂S$H_2S$. The pH at which the metal sulphide YS will form as a precipitate is ____ (Nearest integer) (Given : Kₛₚ(XS) = 1 × 10⁻²²$K_{sp}(XS) = 1 \times 10^{-22}$ at 25°C$25^{\circ}\text{C}$, Kₛₚ(YS) = 4 × 10⁻¹⁶$K_{sp}(YS) = 4 \times 10^{-16}$ at 25°C$25^{\circ}\text{C}$, [H₂S] = 0.1 M$[H_2S] = 0.1 \text{ M}$ in solution, Kₐ₁ × Kₐ₂(H₂S) = 1.0 × 10⁻²¹$K_{a1} \times K_{a2}(H_2S) = 1.0 \times 10^{-21}$, 2 = 0.30$\log 2 = 0.30$, 3 = 0.48$\log 3 = 0.48$, 5 = 0.70$\log 5 = 0.70$)

For the given reaction, choose the correct expression of KC$K_C$ from the following :- Fe(aq)³⁺ + SCN(aq)⁻ leftharpoons (FeSCN)(aq)²⁺$$Fe_{(aq)}^{3+} + SCN_{(aq)}^{-} \rightleftharpoons (FeSCN)_{(aq)}^{2+}$$