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: Surgery
Muscle most commonly affected by congenital absence is? 
Select and explain. 
A. Pectoralis major, B. Semi membranosus, C. Teres minor, D. Gluteus maximus
A: Pectoralis major
Answer: A: Pectoralis major 
Explanation: Pectoralis major and minor muscles are the most common congenitally absent muscles in humans. Ref: Ultrasound of the Musculoskeletal System, 2007, Pages 51, 285; Principles of Neurology By Allan H. Ropper, Raymond Delacy Adams, Maurice Victor, Robe H. Brown, Page 1245; Clinical Pediatric Urology By A. Barry Belman, Lowell R. King, Stephen Alan Kramer, Page 947