This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc. (R.B.C), Subject name: Pathology
Direct globulin test is positive in? 
Select and explain. 
A. PNH, B. Sickle cell anemia, C. Thalassemia, D. Paroxysmal cold hemoglobinuria
D: Paroxysmal cold hemoglobinuria
Answer: D: Paroxysmal cold hemoglobinuria 
Explanation: Ans. (d) Paroxysmal cold hemoglobinuria(Ref: Robbins 9th/pg 642; 8th/pg 654)Direct globulin test is positive in Paroxysmal cold hemoglobinuria, as anti P antibody is formed.