This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
Infection/inflammation of all of the following causes enlarged superficial inguinal lymph nodes except 
Select and explain. 
A. Isthmus of uterine tube, B. Inferior pa of anal canal, C. Big toe, D. Penile urethra
D: Penile urethra
Answer: D: Penile urethra 
Explanation: Penile urethra mostly drains into deep inguinal lymphnodes. Ref: Gray's 38e/p-1623