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: Pathology
Finnish of nephrotic syndrome is caused by defect in following protein - 
Select and explain. 
A. Nephrin, B. Podocin, C. Alpha actinin, D. CD2 activated protein
A: Nephrin
Answer: A: Nephrin 
Explanation: . Nephrin