This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Medicine
Injury caused by biopsy taken for scalene lymph node - 
Select and explain. 
A. Injury to phrenic nerve, B. Injury to vagus nerve, C. Injury to apex to lung, D. Injury to trachea
C: Injury to apex to lung
Answer: C: Injury to apex to lung 
Explanation: Posterior lymph nodes are located along the back of the neck. They are known as the lateral jugular, anterior jugular, and jugulo-digastric lymph nodes. The inferior deep cervical lymph nodes, the juguloomohyoid nodes, and the supraclavicular, or scalene, nodes are considered deep jugular nodes some times during the biopsy of scalene lymph nodes causes injury to vagus nerve Ref Davidson 23rd edtion pg 1061