The Two Layers of Tissue in a Hydra Are

The two layers of tissue in a hydra are

A) The epidermis which covers and protects and the inner layer that contains flame cells.
B) The epidermis that covers and protects and the gastrodermis where cells that complete digestion are found.
C) The epidermis that contains flame cells and the gastrodermis that contains the nephridia.
D) The epidermis that covers and protects and the gastrodermis that contains the nephridia.
E) The epidermis that covers and protects and the gastrodermis that contains a ladder-like nervous system.