Final answer:
The acid among the choices is Vinegar, which is acetic acid and reacts with water to form hydronium and acetate ions.
Step-by-step explanation:
The acid among the given choices is c) Vinegar. Vinegar mainly consists of acetic acid (CH3COOH) which is a weak acid. It reacts with water to produce hydronium ions (H3O+) and acetate ions (CH3COO-), as shown in the given chemical equation.
Ammonia (NH3) is a weak base that reacts with water to form ammonium (NH4+) and hydroxide ions (OH-). Water (H2O) is neutral, although it can act as both an acid and a base in different reactions. Sodium hydroxide (NaOH) is a strong base, and its addition to water would not make the water acidic but rather increase its basicity.