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: Medicine
Locate the renal stone with pain radiating to medial side of thigh and perineum due to slipping of stone in males: 
Select and explain. 
A. At pelvic brim, B. Intramural opening of ureter, C. Junction of ureter and renal pelvis, D. At crossing of gonadal vessels and ureter
A: At pelvic brim
Answer: A: At pelvic brim 
Explanation: Answer is A (At pelvic brim): Pain radiating to medial side of thitth and perineum suggetsts a stone in lower poion of ureter (proximal to orifice) or at pelvic brim.