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And I can understand why you think all of them are suitable; however, how would you know by adding aq KOH that a reaction had occurred? A would fizz due to CO2 gas, C would change color, D would fizz due to H2 gas. B would react but how would you know it?
Note: IF the acid were concentrated (very concd) and IF the KOH were concentrated (very concd), then you would be able to tell because the neutralization generates heat.