One of Hans Spemann's Important Experiments Involved

One of Hans Spemann's important experiments involved

A) dividing human embryos into equal halves.
B) killing a single cell in a sea urchin embryo to study the effects.
C) dividing a frog embryo in two using a strand of his daughter's hair.
D) removing cytoplasm from muscle cells and transplanting it into a fertilized egg.
E) All of the above