Which symptom is most likely associated with excess hydrochloric acid in the stomach?

Excess hydrochloric acid in the stomach can lead to gastroesophageal reflux, which occurs when the acid flows back into the esophagus. This backflow can irritate the lining of the esophagus, resulting in symptoms such as heartburn, chest pain, and a sour taste in the mouth. The high acidity can compromise the function of the lower esophageal sphincter, leading to increased episodes of reflux. This link between excess stomach acid and gastroesophageal reflux makes it the most likely associated symptom among the options provided.

While symptoms like indigestion, which is characterized by discomfort in the stomach often accompanied by bloating and nausea, may also occur with excess acid, the direct association between high hydrochloric acid levels and the reflux process makes gastroesophageal reflux the most definitive symptom to highlight in this context.