2010 Destroyer GC 228

[RyenguinLove]

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the explanation considered the indicator was a weak acid, but what if the indicator is a weak acid? the result should be yellow instead of red.

I still think the answer should be E

 

[ToBeDDSS]

The problem says Red is undissociated, therefore this is the protonated form. Yellow is deprotonated form. Since the solution Hal low PH it must be protonated. A is the correct answer.
Hope this helps