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
Intercostobrachial nerve is a branch of - 
Select and explain. 
A. 1st intercostal nerve, B. 2nd intercostal nerve, C. 3rd intercostal nerve, D. Upper trunk of brachial plexus
B: 2nd intercostal nerve
Answer: B: 2nd intercostal nerve 
Explanation: Intercostobrachial nerve
-        Lateral cutaneous branch of 2nd intercostal nerve
-        Supplies

Skin of floor of axilla.
Upper part of medial aspect of arm.