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: Surgery
Cause of hydrocele in infants 
Select and explain. 
A. Patent processus vaginalis, B. Patent gubernaculum, C. Impaired drainage, D. Epididymal cyst
A: Patent processus vaginalis
Answer: A: Patent processus vaginalis 
Explanation: None