This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: AIIMS 2018, Subject name: Surgery
A Young Male complained of intermittent pain , swelling and discharge at the base of spine. He also had episodes of fever and repeated abscesses that had burst spontaneously , in recent past. By occupation , he is a jeep driver. On physical examination, diagnosis of pilonidal sinus was made. Which flap-based procedure is used for pilonidal sinus surgery? 
Select and explain. 
A. Rhomboid flap, B. Circular flap, C. Free flap, D. Rotational flap
A: Rhomboid flap
Answer: A: Rhomboid flap 
Explanation: Pilonidal sinus surgery - excision of pilonidal sinus and cyst and repair of defect by flap. Flaps used: 1. Limber's flap 2.Karydakis flap 3. Rhomboid flap 4. Bascom procedure