**Core Concept:** The Body Mass Index (BMI) is a mathematical index of weight-for-height that is commonly used to categorize adults as underweight, normal weight, overweight, or obese. BMI is calculated by dividing an individual's weight (in kilograms) by the square of their height (in meters).

**Why the Correct Answer is Right:** The normal range of BMI is considered between 18.5 and 24.9. This range indicates that an individual has a healthy weight according to their height and body composition. The calculation helps identify individuals who may be at risk for health complications due to underweight, overweight, or obesity.

**Why Each Wrong Option is Incorrect:**

A. 18.5 - 24.9: This is the correct range, so any option within this range is correct.
B. 24.9: This range indicates overweight and obesity, increasing the risk of health problems.
D. > 30: This is the range for obese individuals and is associated with significant health risks.

**Clinical Pearl / High-Yield Fact:** While BMI is a useful tool for screening purposes, it has limitations due to not considering factors such as muscle mass, body fat distribution, and age. It is crucial to consider these factors while interpreting BMI results and making clinical decisions.

**Correct Answer:** 18.5 - 24.9