## Core Concept
The pH of drinking water is a measure of its acidity or alkalinity. The pH scale ranges from 0 to 14, with a pH of 7 being neutral, below 7 being acidic, and above 7 being alkaline. The acceptable pH range for drinking water is slightly related to its safety and taste.

## Why the Correct Answer is Right
The correct pH range for drinking water is between 6.5 and 8.5. This range is considered safe for consumption and is often recommended by health and environmental agencies. A pH of 7 is neutral and is the middle point of this range.

## Why Each Wrong Option is Incorrect
- **Option A:** A pH range of 0-6.5 indicates acidic water, which, while not harmful in terms of pH alone, can be corrosive and leach metals from pipes.
- **Option B:** A pH range of 8.5-14 indicates alkaline water. While not typically harmful, very alkaline water can have a bitter taste and may cause mineral imbalances.
- **Option D:** A pH of "0" is highly acidic and corrosive, equivalent to the pH of hydrochloric acid, which is not suitable for drinking.

## Clinical Pearl / High-Yield Fact
A key point to remember is that the pH of drinking water can affect its taste and potential to cause corrosion in water pipes. However, for human health, the pH itself is less critical than contaminants like heavy metals, bacteria, or viruses.

## Correct Answer: C. 6.5-8.5.