This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head and neck blood supply and scalp, Subject name: Anatomy
Exposure of left subclan aery by supraclavicular approach does NOT require cutting of: 
Select and explain. 
A. Sternocleidomastoid, B. Scalenus anterior, C. Scalenus medius, D. Omohyoid
C: Scalenus medius
Answer: C: Scalenus medius 
Explanation: Scalenus medius muscle lies postero-inferior to subclan aery and is not required to be cut.