<prompt> A newborn has multiple congenital defects owing to dysgenesis of neural crest cells. Which of the following cells is most likely to be sparedMelanocytesMotor neuronsParafollicular cellsSpinal ganglion cells  <response>: Motor neurons option 2 develop from neural tube Neural plate ectoderm, hence may not be affected in dysgenesis of neural crest cells NCCs. Melanocytes option 1 , Parafollicular cells option 3 or spinal ganglion cells option 4 are derived from NCCs, and are compromised in this scenario. 