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
From which of the following does' nucleus pulposus is formed: 
Select and explain. 
A. A, B. B, C. C, D. D
D: D
Answer: D: D 
Explanation: Ans. D. (D).Nucleosus pulposus is formed from notochord which has been shown in image as Da. Notochord develops in region lying between the cranial end of the primitive streak and the caudal end of the prochordal plateb. The notochordal process develops from Notochordc. Structural changes of notochord are shown in the below diagram