This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Development period- week 1,2,3,4, Subject name: Anatomy
The prochordal plate marks the site of the future 
Select and explain. 
A. Umbilical cord, B. Hea, C. Mouth, D. Anus
C: Mouth
Answer: C: Mouth 
Explanation: The prochordal plate is a circular, midline thickening of hypoblast cells that are firmly attached to the overlying epiblast cells. The plate will eventually develop into a membrane called the Buccopharyngeal membrane at the site of the future mouth.