All are true regarding trachea except:
**Core Concept**
The trachea, also known as the windpipe, is a vital part of the respiratory system, connecting the pharynx to the bronchi. It is a muscular tube lined with ciliated pseudostratified columnar epithelium, which maintains airway patency by trapping dust and debris.
**Why the Correct Answer is Right**
The correct answer will be a statement that is true regarding the trachea. This could involve its anatomy, histology, or physiological functions. The trachea's diameter is approximately 2.5 cm in adults, and it is supported by 16-20 C-shaped cartilaginous rings. The trachea also contains mucous glands and lymphoid tissue, such as the tracheal tonsils.
**Why Each Wrong Option is Incorrect**
**Option A:** This statement could be false if it contradicts the anatomical or physiological properties of the trachea.
**Option B:** This option might be incorrect if it inaccurately describes the histological characteristics of the tracheal epithelium or the composition of the cartilaginous rings.
**Option C:** This choice could be wrong if it misrepresents the trachea's role in the respiratory system or its relationship with neighboring structures.
**Clinical Pearl / High-Yield Fact**
A key clinical correlation is that the trachea's narrowest portion is at the cricotracheal junction, making this area susceptible to obstruction during intubation or in cases of tracheal stenosis.
**Correct Answer:** A.