In a survey, many children are examined and were found to have urogenital abnormalities. Which congenital anomaly is associated with an increased risk of bladder carcinoma?: (A) Medullary sponge kidney, (B) Bladder exstrophy, (C) Unilateral renal agenesis, (D) Double ureter
Answer is B. Congenital anomalies associated with an increased risk of bladder cancer are:

patent urachus
exstrophy bladder

Both increase the risk for adenocarcinoma.