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
[{'content': 'Buccopharyngeal membrane consist of \nSelect and explain. \nA. Mesoderm and endoderm, B. Ectoderm and mesoderm, C. Ectoderm, mesoderm and endoderm, D. Endoderm and ectoderm', 'role': 'user'}, {'content': "Answer: D \nExplanation: There is no mesoderm in the prochordal plate, so this region remains relatively thin, and later forms the buccopharyngeal membrane. The buccopharyngeal membrane breaks at 4th week . The mouth is bidermal in development. It is derived paly from the stomatodeum (ectodermal) and paly from the cranial pa of the foregut (endodermal). Hence its epithelial lining is paly ectodermal and paly endodermal and the demarcation between the two is buccopharyngeal membrane. Ref: Inderbir Singh's Human Embryology, eleventh edition, pg. no.,68,69,163.", 'role': 'assistant'}]