This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Upper limb, Subject name: Anatomy
Which of the following muscle is not in the pectoral region? 
Select and explain. 
A. Pectoralis major, B. Infraspinatus, C. Pectoralis minor, D. Subclavius
B: Infraspinatus
Answer: B: Infraspinatus 
Explanation: Muscles of pectoral region:- Pectoralis major , pectoralis minor , subclavius and serratus anterior. Largest muscle of pectoral region- pectorals major. Key muscle- pectoralis minor. Infraspinatus- muscle of scapular region. {Reference: vishram singh, page no.40, chapter 3}