Answer:
B
Step-by-step explanation:
Neutralization reaction is where you add equal moles or quantity of acid and base so that they both neutralize each other or "cancel" each other making the pH to be neutral which is 7. Group B is likely wrong as their pH is 5 which means they added too much acid, if they had equal acid and base their pH would be 7 however since they added more acid, there was still some acid left after the initial neutralization and this acid decreased the pH to 5.