This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Contraceptives, Subject name: Gynaecology & Obstetrics
A 34-year-old male undergoes vasectomy. Which of the following is the most frequent immediate complication of this procedure? 
Select and explain. 
A. Infection, B. Impotence, C. Hematoma, D. Spontaneous reanastomosis
C: Hematoma
Answer: C: Hematoma 
Explanation: Vasectomy is performed by isolating the vas deferens, cutting it, and closing the ends by either fulguration or ligation. Complications that may arise include hematoma in up to 5% of subjects, sperm granulomas (inflammatory responses to sperm leakage), spontaneous reanastomosis, and, rarely, infections. Sexual function following healing is rarely affected.