This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Larynx, Subject name: ENT
[{'content': 'Which of the following cailage has signet ring shape \nSelect and explain. \nA. Thyroid, B. Cricoid, C. Cuneiform, D. Arytenoid', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Cricoid has a signet ring shape and is the only cailage forming a complete ring. Its posterior pa is expanded to form a Lamina while anteriorly it is narrow forming an Arch. Whereas in thyroid-the two alae meet anteriorly forming an angle 90 degrees in males & 120 degrees in females. Cuneiform is rod-shaped and Arytenoid is pyramidal in shape. Ref: Textbook of diseases of ENT, PL Dhingra, 7th edition, pg no. 319', 'role': 'assistant'}]