This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Neck Triangles and parotid gland, Subject name: Anatomy
Structure piercing investing layer of deep cervical fascia in posterior triangle of neck 
Select and explain. 
A. Spinal accessory nerve, B. Common carotid aery, C. Internal jugular vein, D. External jugular vein
D: External jugular vein
Answer: D: External jugular vein 
Explanation: Investing layer in the posterior triangle of neck is pierced by: * External jugular vein * Supraclavicular nerves. * Cutaneous nerves including lymphatics.