For the redox reaction, ${\mathrm{MnO}}_4^{-}+{\mathrm{C}}_2{\mathrm{O}}_4^{2-}+{\mathrm{H}}^{+}\to {\mathrm{Mn}}^{2+}+{\mathrm{CO}}_2+{\mathrm{H}}_2\mathrm{O},$ the correct coefficients of the reactions for the balanced reaction are:

$\begin{array}{l}{\mathrm{MnO}}_4^{-}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}{\mathrm{C}}_2{\mathrm{O}}_4^{2-}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}{\mathrm{H}}^{+}\end{array}$
2                  5           16

$$\begin{gathered} \begin{array}{l}{\mathrm{MnO}}_4^{-}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}{\mathrm{C}}_2{\mathrm{O}}_4^{2-}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}{\mathrm{H}}^{+}\end{array} \\ 16 5 2 \end{gathered}$$

$$\begin{gathered} \begin{array}{l}{\mathrm{MnO}}_4^{-}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}{\mathrm{C}}_2{\mathrm{O}}_4^{2-}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}{\mathrm{H}}^{+}\end{array} \\ 5 16 2 \end{gathered}$$

$$\begin{gathered} \begin{array}{l}{\mathrm{MnO}}_4^{-}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}{\mathrm{C}}_2{\mathrm{O}}_4^{2-}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}\hspace{0.25em}{\mathrm{H}}^{+}\end{array} \\ 2 16 5 \end{gathered}$$