${\mathrm{H}}_2{\mathrm{O}}_2$ is manufactured these days

• A

  By the action of ${\mathrm{H}}_2{\mathrm{O}}_2$ on ${\mathrm{BaO}}_2$

• B

  By the action of ${\mathrm{H}}_2{\mathrm{SO}}_4 \mathrm{on} {\mathrm{Na}}_2{\mathrm{O}}_2$

• C

  By electrolysis of 50% ${\mathrm{H}}_2{\mathrm{SO}}_4$

• D

  By burning hydrogen in excess of oxygen