E-cool is a bacterium that occurs naturally in the intestines of people and animals
Answer: Option A) Cells
Explanation:
The soft lining inside the mouth is an example of cell.
The inner lining of mouth is made up of the mucous membrane. Soft lining is consist of squamous epithelium also called as oral epithelium, which is a type of cell.
Epithilial cells are arranged in layers upon a basal membrane. It function to protect mouth against abrasion.
Hence the correct option is A) cells.
