How do you calculate Body Mass Index (BMI)?

The Body Mass Index (BMI) is a widely used tool to assess body weight relative to height, helping to categorize individuals into different weight classifications (underweight, normal weight, overweight, and obesity). The correct method of calculating BMI is by taking a person's weight in kilograms and dividing it by their height in meters squared.

This calculation is fundamental because it provides a standardized way to evaluate body weight without being influenced by variations in body composition that can occur with muscle mass, fat distribution, or hydration levels. The formula used can be expressed as:

[ \text{BMI} = \frac{\text{Weight (kg)}}{\text{Height (m)}^2} ]

This approach is primarily based on the metric system, which is commonly used in scientific and medical contexts. By using weight in kilograms and height in meters, the resulting BMI value allows for uniform interpretation across different populations.

The other options present different calculations that do not conform to the standard BMI formula: they might use incorrect units or inversely relate height and weight, which would not yield an accurate assessment of body mass relative to height. Thus, the correct method is supported by both its scientific validity and its relevance in public health guidelines worldwide.