The tissue that forms the outer surface of the body is a stratified squamous keratinized epithelium. The surface layer of dead cells(stratum corneum) is made to keep things out of the body, protecting it. The tissue that lines the digestive tract(e.g. intestine). Is made from 1 layer of columnar cells that facilitate the absorption of nutrients. Both tissues are epithelia.
I think all three ideas should be selected since they were all in the blue box so it seems like it’s included
This is called mutualism. hope this helpes