$M_2SO_4$ ($M^+$ is monovalent metal ion) has a $K_{sp}$ of $3.2 \times 10^{-5}$ at 298 K. The maximum concentration of $SO^{2-}_4$ ion that could be attained in a saturated solution of this solid at 289 K is

Question

(a) $3 \times 10^{-3}$ M

(a) $7 \times 10^{-2}$ M

(b) $2.89 \times 10^{-4}$ M

(c) $2 \times 10^{-2}$ M