Heartburn or gastroesophageal reflux disease is caused when
Oesophagus is open during swallowing
movement of food from the pharynx into the esophagus is altered
the gastro-esophageal sphincter does not completely close
None of the above
When the gastro-esophageal sphincter does not completely close, the stomach’s contents can reflux (that is, back up into the esophagus), causing heartburn or gastroesophageal reflux disease (GERD). Hence, the correct answer is option c.