Acidity Ranking confusion

[dragonfruit95]

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Hey everyone, I'm a little confused about this question involving acid ranking I found online. I understand that C is the least acidic, but unsure about A & B. The solutions say A cannot be stabilized by resonance, which I think resonance is possible.

 

[Syxx]

You are right. It's a mistake on the site, if you look carefully at the solutions you'll see that the structure they draw the resonance structures for is actually the conjugate base of compound A.