Every mucosa consists of:
a. a simple epithelium.
b. a stratified epithelium.
c. a surface epithelium together with associated glands.
d. a surface epithelial layer, with or without glands, together with an underlying layer of loose connective tissue.
e. a surface epithelial layer, with or without glands, together with an underlying layer of loose connective tissue, and a layer of smooth muscle.