This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
Runt disease is due to 
Select and explain. 
A. Hypogammaglobulinemia, B. GVHD, C. Autoimmunity, D. Immunosuppression
B: GVHD
Answer: B: GVHD 
Explanation: Runt disease is graft versus host disease produced experimentally in Laboratory animals.