A Most common tumor of the urinary bladder is -: (A) Sq. cell carcinoma, (B) Adeno carcinoma, (C) Transitional carcinoma, (D) Str. squamous carcinoma
Answer is C. There are 3 common histological types of bladder cancer 

Transitional (urothelial) cell ca - ~90%
Squamous cell ca - ~5-10%
Adenocarcinoma - ~2%