The Standard Free Energy of Formation $\Delta G _ { f } ^ { 0 }$

The standard free energy of formation, $\Delta G _ { f } ^ { 0 }$ , of atomic oxygen is 230.1 kJ/mol. Determine the equilibrium constant for the following reaction at standard thermodynamic conditions.
O₂(g) $\leftrightarrows$ 2O(g)

A) 4.7 *10^-41
B) 2.3 *10^-61
C) 2.2 *10^-81
D) 2.1 * 10⁴⁰
E) 4.5 * 10⁸⁰