Final answer:
The correct answer is b. Vinegar, which contains acetic acid, making it an acid rather than a base or neutral substance like the other options listed.
Step-by-step explanation:
The question which asks for identification of an acid from a given list is a common type of inquiry in the field of chemistry. Among the options listed (a. Ammonia, b. Vinegar, c. Water, d. NaOH), the correct answer is b. Vinegar. Vinegar contains acetic acid (CH3COOH), which is a weak acid. It is this component of vinegar that gives it its sour taste and the ability to act as an acid in chemical reactions.
Option a, Ammonia (NH3), is a weak base. Option c, Water (H2O), is neutral, although it can act as either an acid or a base depending on the reaction it is involved in. Option d, Sodium Hydroxide (NaOH), is a strong base, not an acid.