This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
Tympanic membrane is derived from which layer? 
Select and explain. 
A. Ectoderm, B. Endoderm, C. Mesoderm, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: HUMAN EMBRYOLOGY-INDERBIR SINGH TENTH EDITION-PAGE NO:372 Tympanic membrane This is formed by the apposition of the tubotympanic recess and the first ectodermal cleft ,these two forming the inner(endodermal)and outer(ectodermal) epithelial linings of the membrane.the intervening mesoderm forms the connective tissue basis