This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Oesophagus, Subject name: Surgery
What is the instrument shown below? 
Select and explain. 
A. Urethral dilator, B. Tracheal dilator, C. Aneurysm needle, D. Urethral dilator
B: Tracheal dilator
Answer: B: Tracheal dilator 
Explanation: Ans. (b) Tracheal dilator* Used during tracheostomy* Smooth and round tip (Not sharp)* Tips bent at right angles to rest of the instrument* No lock or clasp* This is known as Trousseau's Tracheal dilator* Helps to widen trachea while inserting tube