Which of the following is not an acid-base neutralization reaction?

a.) nh3 + hcl nh4cl

b.) hcl + nabr hbr + nacl

c.) hcl + hbr h2 + clbr

d.) 2 hbr + ca(oh)2 cabr2 + 2 h2o

HCl + HBr H2 + ClBr is not acid and base reaction.

During electrolysis:
NH3(g) + HCl(aq) = NH4Cl(aq) or 
NH3(g) + H3O+(aq) +Cl^1-(aq) = NH4+(aq) + Cl1-(aq) 
add OH1- add H3O+ 
NH4OH + HCl
Hence,
The best answer is :
C.) HCl + HBr H2 + ClBr