This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax, Subject name: Anatomy
Superior intercostal aery is a branch of 
Select and explain. 
A. Costocervical trunk, B. Dorsal scapular aery, C. Thyrocervical trunk, D. Internal thoracic aery
A: Costocervical trunk
Answer: A: Costocervical trunk 
Explanation: Superior intercostal arery is a branch of costocervical trunk of subclan aery. BD chaurasia's human anatomy.6th edition volume 1.page no 219.