While $$Fe^{3+}$$ is stable, $$Mn^{3+}$$ is not stable in acid solution because

A

$$O_2$$ oxidises $$Mn^{2+}$$ to $$Mn^{3+}$$

B

$$O_2$$ oxidises both $$Mn^{2+}$$ to $$Mn^{3+}$$ and $$Fe^{2+}$$ to $$Fe^{3+}$$

C

$$Fe^{3+}$$ oxidises $$H_2O$$ to $$O_2$$

D

$$Mn^{3+}$$ oxidises $$H_2O$$ to $$O_2$$