<prompt> Which of the following is not a neural crest derivative?Ciliary muscleMelanocytesCiliary ganglionSphincter pupillae  <response>: Sphincter pupillae is derived from neurectoderm not mesenchyme or neural crest cell Neural Crest Derivatives: Corneal Keratocytes Ciliary muscles Corneal stroma and endothelium endothelial cells and keratocytes Pericytes of choroidal membranes Melanocytes Ciliary ganglion Stroma of Iris and choroid Trabecular meshwork extraocular muscles are mesodermal in origin 