This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Diagnosis in Obstetrics, Subject name: Gynaecology & Obstetrics
The following curve is used in evaluation to 
Select and explain. 
A. Non progression of labor, B. Fetal distress, C. Rh incompatibility, D. Fetal maturity
C: Rh incompatibility
Answer: C: Rh incompatibility 
Explanation: Ans. C. Rh incompatibilityThe image shows Lily's curve, which is used to predict the severity of fetal hemolysis.The optical density of liquor containing bilirubin pigment is observed at wavelength 250-700nm. In presence of bilirubin, there is a deviation bulge/peak at 450nm. Bigger the bulge, more is the effect on the fetus.