## **Core Concept**
The bevel of endotracheal tubes is a critical design feature that facilitates easier passage through the vocal cords during intubation. The bevel's orientation affects the tube's direction and ease of insertion.

## **Why the Correct Answer is Right**
The bevel is positioned on the left side at the proximal tip of the tube to facilitate easier passage through the vocal cords, particularly during direct laryngoscopy. This left-sided bevel allows the tube to pass more easily into the right mainstem bronchus, which is the more direct path. The design takes into account the anatomical alignment of the trachea and the main bronchi, making intubation smoother and reducing the risk of endobronchial intubation.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Not specified, but any option suggesting a right-sided bevel or no bevel would be incorrect due to the anatomical reasons mentioned.
- **Option B:** Similarly, not specified, but if suggesting a different orientation or no specific orientation, it would be incorrect based on standard intubation practices.
- **Option D:** If suggesting a different side or no bevel, it would be incorrect for the same anatomical and practical reasons.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that the left-sided bevel on endotracheal tubes helps in reducing the risk of accidental intubation of the esophagus or endobronchial intubation, making it a critical feature for safe airway management.

## **Correct Answer:** B. To facilitate passage through vocal cords and to prevent endobronchial intubation on right side.