This System of Chemicals, ,Act as a Buffer in the Blood.If

This system of chemicals, ,act as a buffer in the blood.If hydrogen ions are added to blood which of the following reactions would occur?

A) $\mathrm { H } ^ { + } + \mathrm { HCO } _ { 3 } ^ { - } \longrightarrow \mathrm { H } _ { 2 } \mathrm { CO } _ { 3 }$
B) $\mathrm { OH } + \mathrm { H } _ { 2 } \mathrm { CO } _ { 3 } \longrightarrow \mathrm { HCO } _ { 3 } ^ { - } + \mathrm { H } _ { 2 } \mathrm { O }$