input: The following are multiple choice questions (with answers) about medical knowledge.   **Question:** 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?   (A) Rhomboid flap   (B) Circular flap   (C) Free flap   (D) Rotational flap
output: ['(A) Rhomboid flap <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Rhomboid flap  (B) Circular flap  (C) Free flap  (D) Rotational flap <> possible answers', '  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? <> context']