In a Classical Experiment,a Portion of an Amphibian Gastrula Was

Multiple Choice

In a classical experiment,a portion of an amphibian gastrula was transplanted to the belly region of another embryo,resulting in the formation of a secondary embryo organized by the graft from host tissue.The equivalent area of the human embryo that would be expected to have similar organizer activity is what structure?

A) Node
B) Somites
C) Cardiac mesoderm
D) Cloacal membrane
E) Body fold