Primitive streak develops from:

B i.e. EpiblastRef: Essentials of Human Embryology, A.K. Datta, 5th edition, 2005, page 38-42Explanation:Primitive StreakAppears about 15th day of development.Formed by active migration and invagination of p ectodermal cells ( into the space between epiblast and hypoblast.Gastrulation^-Tbe process of invagination of pleuripotent cells in between epiblast and hypoblast.Primitive streak acts as primary organizer- Induces the differentiation of notochord and intraembryonic mesoderm.Primitive streak from its cranial end gives origin to definitive notochord-forerunner in the development of vertebral column.Notochordal cells persist as nucleus pulposus in the center of intervertebral disc.Primitive streak disappears at 26th day of development.If persist gives the development of sacrococcygeal teratoma.