Imagine that you find a fossil skeleton of a Late Devonian vertebrate.Which feature would enable you to conclude that it was fully a tetrapod?

A) a flattened skull with dorsally facing orbits
B) the loss of skeletal support for any gills
C) the loss of dorsal and anal fins
D) well-developed joints between vertebrae, and between vertebrae and the pelvis
E) lungs to enable breathing of atmospheric oxygen