This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pharyngeal Arches, Subject name: Anatomy
Digeorge syndrome is due to defect of? 
Select and explain. 
A. pouch 1, B. pouch 2, C. pouch 3 and 4, D. pouch 5
C: pouch 3 and 4
Answer: C: pouch 3 and 4 
Explanation: Digeorge syndrome is due to defect of pouch 3 and 4. Pouch 3 compromised - No thymus - CMI decreases - Severe bacterial infections Pouch 3 & 4 compromised - absent or poorly developed parathyroid - low PTH - Hypocalcemia.