Which of the following is only a redox reaction but not a...

Options

1. A$4 \mathrm{H}_3 \mathrm{PO}_3 \rightarrow 3 \mathrm{H}_3 \mathrm{PO}_4+\mathrm{PH}_3$
2. B$2 \mathrm{H}_2 \mathrm{O}_2 \rightarrow 2 \mathrm{H}_2 \mathrm{O}+\mathrm{O}_2$
3. C$\mathrm{P}_4+3 \mathrm{NaOH}+3 \mathrm{H}_2 \mathrm{O} \rightarrow 3 \mathrm{NaH}_2 \mathrm{PO}_2+\mathrm{PH}_3$
4. D$\mathrm{P}_4+8 \mathrm{SOCl}_2 \rightarrow 4 \mathrm{PCl}_3+2 \mathrm{ S}_2 \mathrm{Cl}_2+4 \mathrm{SO}_2$