Compound $A$ reacts with $NH_4Cl$ and forms a compound $B$. Compound $B$ reacts with $H_2O$ and excess of $CO_2$ to form compound $C$,which on reaction with saturated $NaCl$ solution forms sodium hydrogen carbonate. Compounds $A, B$ and $C$ are respectively:

• A
  $CaCl_2, NH_3, NH_4HCO_3$
• B
  $CaCl_2, NH_4^+, (NH_4)_2CO_3$
• C
  $Ca(OH)_2, NH_3, NH_4HCO_3$
• D
  $Ca(OH)_2, NH_4^+, (NH_4)_2CO_3$