Answer
B. CH3COOH and NaCH3COO⁻
Explanation
By definition, a buffer is a solution of a weak acid and conjugate base or a weak base and conjugate acid used to resist pH change with added solute.
However, acidic buffers are solutions that have a pH below 7 and contain a weak acid and one of its salts.
Therefore, the combination that would act as an acidic buffer among the given options is:
B. CH3COOH and NaCH3COO
