During gastrulation in frogs, a rod of mesoderm under the dorsal surface forms the

Notochord

During gastrulation in frogs, a rod of mesoderm under the dorsal surface develops into the notochord which is the precursor of the backbone. The notochord plays an important structural role by serving as the axial skeleton of the embryo until other elements such as the vertebrae forms.

i think the answer is b.

hope it

weathering is the answer.