The reaction involved during the removal of temporary hardness of water is:
A. `2CaCl_(2)+(NaPO_(3))_(6)rarrNa_(2)(Ca_(2)(PO_(3))_(6))+4NaCl`
B. `CaCl_(2)+Na_(2)CO_(3)rarrCaCO_(3)downarrow+2NaCl`
C. `MgSO_(4)+Na_(2)Al_(2)Si_(2)O_(4)xH_(2)OrarrMgAl_(2)O^(7)xH_(2)O+Na_(2)SO_(4)`
D. `Ca(HCO_(3))_(2)overset(Delta)rarrCaCO_(3)+H_(2)O+CO_(2)downarrow`
