**Core Concept**
The OHI (Occlusal Hygiene Index) is a tool used to assess the status of occlusal (chewing) surfaces of teeth for the presence and extent of dental plaque and calculus. It is an essential parameter in evaluating oral hygiene practices and their impact on oral health.

**Why the Correct Answer is Right**
The OHI assesses the extent of dental plaque and calculus on the occlusal surfaces of teeth. It is a subjective measure that takes into account the amount of plaque and calculus present, as well as their distribution on the teeth. The OHI scoring system ranges from 0 to 3, with higher scores indicating poorer oral hygiene. The correct range of OHI scores is from 0 to 3.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not provided, but it is likely that the range of OHI scores is being questioned. Without the options, we cannot provide a direct comparison.
**Option B:** This option is not provided, and without it, we cannot assess its accuracy.
**Option C:** This option is not provided, and without it, we cannot assess its accuracy.

**Clinical Pearl / High-Yield Fact**
For dental students and general practitioners, it is essential to remember that the OHI scoring system is subjective and may vary between examiners. However, when using the OHI, it is crucial to be consistent in scoring to ensure accurate assessments of oral hygiene practices.

**Correct Answer:** 0-3. The OHI scores range from 0 to 3, with higher scores indicating poorer oral hygiene.