The answer to Q5 is B but what would be the reasoning behind it? I know I use the Henderson-Hasselbalch equation where pH=pKa and it is true for B, but A would also be true wouldn’t it?

The answer to Q5 is B but what would be the reasoning behind it I know I use the HendersonHasselbalch equation where pHpKa and it is true for B but A would also class=