A renal mass seen on prenatal check up is most probably -

Ans. is 'b' i.e., Mesoblastic nephromaEnlargement of a kidney on prenatal imaging is usually due to hydronephrosis or a cystic renal enlargement, such as multicystic dysplastic kidney or polycystic kidney disease.Solid tumors of the kidneys are rarely seen in the antenatal period, but can be diagnosed by ultrasound. Most common solid tumour is Mesoblastic nephroma