At 1500 K the standard Gibbs energies of formation of oxides, per mole of $\mathrm{O}{}_2$ consumed, are (in $\mathrm{kJ}$): $2\mathrm{Fe}+\mathrm{O}{}_2\to 2\mathrm{FeO}$, $-380$; $2\mathrm{Zn}+\mathrm{O}{}_2\to 2\mathrm{ZnO}$, $-390$; $2\mathrm{C}+\mathrm{O}{}_2\to 2\mathrm{CO}$, $-440$; $\frac{4}{3}\mathrm{Al}+\mathrm{O}{}_2\to \frac{2}{3}\mathrm{Al}{}_2\mathrm{O}{}_3$, $-870$. Treat the values as constant and ignore any change of state. At 1500 K, which reductions are thermodynamically feasible?

1. A$\mathrm{ZnO}$ is reduced to Zn by carbon (forming $\mathrm{CO}$)
2. B$\mathrm{FeO}$ is reduced to Fe by carbon (forming $\mathrm{CO}$)
3. C$\mathrm{ZnO}$ is reduced to Zn by iron
4. D$\mathrm{ZnO}$ is reduced to Zn by aluminium