INFORMATION:
We have the next options:
A. It prevents a salt from forming in solution.
B. It resists a change in pH when H* or OH is added to a solution.
C. It prevents an acid or base from being neutralized.
D. It prevents an acid-base reaction from happening.
And we must select the one that describes what a buffer do
STEP BY STEP EXPLANATION:
A buffer is a mixture of a weak acid and its conjugate base or a mixture of a weak base and its conjugate acid.
A buffer resists change in pH by accepting hydrogen ions when acids are added to the solution and donating hydrogen ions when bases are added.
Knowing that, we can state that a buffer resists a change in pH when strong acid (H+) or strong base (OH-) is added to a solution.
ANSWER:
B. It resists a change in pH when H* or OH is added to a solution.