A 4-week-old male infant presents with progressive projectile non-bilious vomiting after feeds. The baby appears dehydrated but is eager to feed after each vomiting episode. On examination, visible gastric peristalsis is noted and a small olive-shaped mass is palpated in the epigastrium. What is the most likely diagnosis?
B
Infantile hypertrophic pyloric stenosis
C
Malrotation with volvulus