Answer:
Concentration of protons will decrease
Explanation:
CH₃COOH + H₂O → CH₃COO⁻ + H₃O⁺
In a medium of water, acetic acid donates its proton to water, to increase the [H₃O⁺]
When we a add a strong base, like NaOH, this also dissociates as this:
NaOH → Na⁺ + OH⁻
As we are adding OH⁻, they will bond to H₃O⁺ so they be neutralized and they will produce water, that's why the [H₃O⁺] will decrease.
2H₂O ⇄ H₃O⁺ + OH⁻ Kw