Colicky abdominal pain, Early onset of vomiting, Palpable mass and bleeding per rectum in a child most strongly suggest.

Intussusception

Appendicitis

Hirschsprung's disease

Meckel's diverticulum

Explanation

Those symptoms are classic signs of intussusception, where one segment of the intestine invaginates into another, often leading to obstruction and ischemia.

It's commonly seen in infants and young children.