Which of the following helps in diagnosis of Laryngopharyngeal reflux

Answer- B. Lower esophageal & pharyngeal pH monitoringIaryngopharyngeal reflux (LPR) is defined as the retrograde flow ofstomach content to the larynx and pharynx whereby this material comes in contact with the upper aerodigestive tract. In contrast, gastroesophageal reflux disease (GERD) is the flow of stomach acids back into the esophagus.Multichannel intraluminal impedance and pH-monitoring studies are most useful in confirming LPR and assessing the magnitude of the problem. Demonstration of reflux events is best achieved with ambulatory multichannel intraluminal impedance (MCII) and pH-monitoring studies.24 hour dual probe pH monitoring (simultaneous esophageal and pharyngeal pH) is used more often.