Q1. Correct answer: C. Esophagogastric junction outflow obstruction.
Rationale
Recent studies recognized the role of medications in inducing esophageal motor disorders. Opiates have been shown to be associated with esophagogastric junction outflow obstruction, achalasia (not type 1), and other hypercontractile esophageal abnormalities.
Reference
Camilleri M et al. Clin Gastroenterol Hepatol. 2017 Sep;15(9):1338-49.