This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Embryology, Subject name: Anatomy
Development of the urinary bladder is from- 
Select and explain. 
A. Urogenital Sinus, B. Paramesonephric Duct, C. Metanephric Blastema, D. Proctodaeum
A: Urogenital Sinus
Answer: A: Urogenital Sinus 
Explanation: Ans. is 'a' i.e., Urogenital Sinus * The urinary bladder (except trigone) is derived from vesicourethral canal, cranial part of urogenital sinus (endodermal). Trigone is derived from Absorbed part of Wolffian duct/mesonephric duct (mesodermal).