Which of the Following Is the Approach Prescribed by the DSM-5

Which of the following is the approach prescribed by the DSM-5 to determine whether a girl suspected of anorexia nervosa is indeed significantly underweight?

A) She can be considered significantly underweight if she is less than 100 pounds.
B) She can be considered underweight if her BMI is below 17.
C) She can be considered underweight if her BMI is below the 5th percentile for other girls her age.
D) A diagnosis of anorexia nervosa would be categorically excluded if she were above the 5th percentile for weight when compared with other girls her age.