Ans. is 'a' i.e., Neuro blastoma MC intra abdominal solid tumor in children.Derived from neural crest.90% present before 5 years of age.50% present before 2 years of age.MC soft tissue sarcoma in children < 15 years of age.Half present below 5 years.2/3 present below 10 years.o Wilm's tumor (Nephroblastoma)Most common malignant tumor of kidney.80% of tumor present below' 5 year of age.o PresentionAsymptomatic abdominal mass (M.C.).Haematuria (10-25%).Hypertension (25%).Abdominal pain (30%).Fever (20%).