This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
Appendix of testis is derived from which of the embryonic structures given below? 
Select and explain. 
A. Paramesonephric duct, B. Mesonephric duct, C. Hind gut, D. Cloaca
A: Paramesonephric duct
Answer: A: Paramesonephric duct 
Explanation: The appendix testis (or hydatid of Morgagni) is a vestigial remnant of the Mullerian duct (Paramesonephric Duct), present on the upper pole of the testis and attached to the tunica vaginalis. It is present about 90% of the time.