The compound that will react with sodium hydroxide to form salt and water is

Correct answer: CH₃CH₂COOH

Explanation: Sodium hydroxide neutralizes carboxylic acids to form a salt and water:
CH₃CH₂COOH + NaOH → CH₃CH₂COONa + H₂O.

• C₆H₁₂O₆ (glucose) — Neutral; does not form a salt with NaOH.
• (CH₃)₃COH (tert-butanol) — Alcohols are very weak acids; no salt + water with NaOH.
• CH₃CH=CH₂ (propene) — Alkene; no acid–base reaction with NaOH.
• CH₃CH₂COOH (propanoic acid) — Correct. Carboxylic acid neutralizes NaOH to give a carboxylate salt and water.