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: Anatomy
Phrenic nerve is 
Select and explain. 
A. Motor nerve to diaphragm, B. Arises chiefly from 3rd cervical nerve, also receives contribution from 4th and 5th cervical nerves, C. The nerve runs vertically on the anterior surface of scalenus anterior, D. It lies anterior to prevertebral fascia
C: The nerve runs vertically on the anterior surface of scalenus anterior
Answer: C: The nerve runs vertically on the anterior surface of scalenus anterior 
Explanation: Phrenic nerve is a mixed nerve, mainly arises from 4th cervical nerve. It lies behind prevertebral fascia and in front of scalenus anterior.