You Are Working with Salamander Embryos in the Early Gastrula

You are working with salamander embryos in the early gastrula stage and transplant cells destined to become neural tissue to a region that would normally form epidermis.As the embryo develops further,you find that the transplanted cells form epidermis instead of neural tissue.You repeat the experiment on a late-stage gastrula and find that as the embryo develops further,the transplanted cells form neural tissue.From these results,you can conclude that the cells being transplanted

A) were differentiated prior to the time they were transplanted in each experiment.
B) were determined to form neural tissue prior to the early gastrula stage.
C) underwent morphogenesis between the early and late gastrula stages.
D) became determined to become neural tissue between the early and late gastrula stages.
E) differentiated into neural tissue between the early and late gastrula stages.