Identifying a Strong Acid

In chemistry, acids and bases are fundamental concepts that describe the behavior and properties of various substances. An acid is typically defined as a substance that can donate a proton (H⁺), while a base is a substance that can accept a proton. The strength of an acid or base can be measured by its pH value, where a lower pH indicates a stronger acid, and a higher pH indicates a stronger base.

Consider the following solutions at room temperature: HCl (hydrochloric acid), NaOH (sodium hydroxide), water, and NH₃ (ammonia). Which of these solutions would be classified as a strong acid?