What statement accurately describes how neural crest cells are induced/specified?
A. Progenitor cells are specified as NCCs when they are in a mesenchymal migratory state and exposed to a high concentration of BMPs
B. NCCs are specified in neural ectoderm in which Wnt, but not BMP. is expressed prior to the formation of the neural tube.
C. NCCs are specified in neural ectoderm in which both Wht and BMP are expressed prior to the formation of the neural tube.
D. Progenitor cells are specified as NCCs when they are in a mesenchymal migratory state and exposed to a high concentration of both BMPs and Wnt