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: ENT
Pseudosulcus in larynx 
Select and explain. 
A. Vocal abuse, B. Tuberculosis, C. Laryngopharyngeal reflux, D. Chronic steroid use
C: Laryngopharyngeal reflux
Answer: C: Laryngopharyngeal reflux 
Explanation: Ans. c. Laryngopharyngeal reflux Pseudosulcus vocalic or laryngeal pseudosulcus is a variable finding in patients with laryngopharyngeal reflux. This sulcus is believed to arise from reflux induced swelling in the subglottic area and is located between the true vocal cords and the suglottic swelling. Laryngeal sulcus Laryngeal Pseudosulcus (Pseudosulcus Vocalis) This sulcus is believed to arise from reflux induced swelling in the subglottic area secondary to laryngotracheal reflux Located between the true vocal cords and the subglottic swelling Laryngeal True sulcus (Sulcus Vergeture) True sulcus is related to scarring of the vocal folds in the phonatory striking zone Located within the true vocal folds at the site of the adherence of vocal fold epithelium to the vocal ligament