<prompt> Preobesity is defined as BMI of: March 200918.5-24.925-29.935-39.940-44.9  <response>: Ans. B: 25-29.9 BMI is an estimate of total body fat mass and is probably the most useful scale to define obesity. Obesity has been defined as a BMI 30.0 kgm2 in World Health Organization WHO classification Body mass index BMI, calculated from measured weight and height, was classified using the World Health Organization categories of underweight BMI 18.5 kgm2, normal weight BMI 18.5 to 24.9 kgm2, pre-obesity PreOB BMI 25 to 29.9 kgm2 and obesity OB BMI 30 kgm2 