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
Carina is situated at which level ? 
Select and explain. 
A. T3, B. T4, C. T6, D. T9
A: T3
Answer: A: T3 
Explanation: Ans. is '13' i.e., T4Trachea bifurcates at carina, at the level of lower border of 7'4 or T4- Ts disc space.Structure Cervico thoracic levelTracheal bifurcation T4-T5Arch of aoa Begins and ends at T4Xiphoid process T9Splenic axis Along 10th ribCarotid bifurcation, Hyoid bone C3Upper border of thyroid cailage C4 Level of cricoids cailageLumbar levelCeliac trunk T12 - L ISuperior mesenteric aery LlTranspyloric plane Lower border of Ll