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
Sphincter and dilator pupillae develop from 
Select and explain. 
A. Mesoderm, B. Surface ectoderm, C. Neuroectoderm, D. Endoderm
C: Neuroectoderm
Answer: C: Neuroectoderm 
Explanation: Muscles of the iris (sphincter and dilator papillae) and myoepithelial cells of the sweat glands are derived from ectoderm.Ref: Human Embryology; Inderbir Singh; Tenth edition; Page no:113