Can become other cells, such as blood cells, nerve cells, and brain cells, when those cells need to be replaced due to damage or wear and tear.

"A cube" is the best model for these cells.

Option B

Explanation:

The model represented in the given figure showcase huge similarities with "Epithelial cells". It is covered under four fundamental animal tissues along with nervous, muscle and connective tissues. Epithelial cells are responsible for forming outer surface of organs and blood vessels and also inner surfaces of cavities in number of internal organs.

Epithelial cells have three principal shapes named as: cuboidal, squamous and columnar. These cells are arranged in single or in double layer or in stratified form with multiple layers.These cells have embedded spherical nuclei present in the center.