Why is indene a stronger acid than indole even though the electronegativity of nitrogen is greater than that of carbon?

• A. Indene is a stronger acid than indole because of the strong inductive effect of nitrogen.
• B. Indene is a stronger acid than indole because of a more electron-deficient carbon atom.
• C. Indene is a stronger acid than indole because it gains aromaticity after deprotonation.
• D. Indene is a stronger acid than indole because azepine loses aromaticity after deprotonation.

Answer: (C)