A 6 week old girl is brought to the physician by her mother because of a 6 day history of vomiting a small amount of milk 2-3 times daily. She appears well. She is at the 50th percentile for length and weight. Physical examination shows no abnormalities. Which of the following is the most likely cause of this patient’s findings?
a) Esophageal spasm
b) Gut malrotation
c) Immature lower esophageal sphincter
d) Neuromuscular abnormality of the esophagus
e) Pyloric stenosis
f) Tracheoesophageal fistula
explanation to the answer ?