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
Contents of posterior triangle of neck 
Select and explain. 
A. Occipital artery, spinal accessory nerve, hypoglossal, ascending pharyngeal artery, B. Occipital artery, lesser occipital nerve, subclavian artery, spinal accessory nerve, C. Occipital artery, spinal accessory nerve, subclavian artery, hypoglossal nerve, D. Occipital artery, Lesser occipital nerve, ascending pharyngeal artery, vagus nerve
B: Occipital artery, lesser occipital nerve, subclavian artery, spinal accessory nerve
Answer: B: Occipital artery, lesser occipital nerve, subclavian artery, spinal accessory nerve 
Explanation: Contents of posterior triangle of neck :

Occipital artery.
Spinal accessory nerve.
Subclavian vessels.
Trunks of brachial plexus.
Great auricular nerve, lesser occipital nerve, supraclavicular nerve, transverse cutaneous nerve.
External jugular vein.