Acell is recognized by other tissue members as "self" by its surface.
(a) glycoproteins
(b) lipids
(c) cholesterol
(d) membrane proteins

(a) Glycoproteins

Explanation:

The glycoproteins are the proteins to which the sugar molecules are attached to. They are present on the cell membrane of the cell. These are very important for cell to cell recognition. It serves as receptor for cell to cell connection as each cell recognize the glycoprotein of it's own tissue type. Thus this helps in connection of cells in the tissue system.

a "theory" a suggestion that is not 100 % accurate, or a figure. some people say its a theory because they of all the passed theory's about one subject. it depends sometimes theory might be accurate and sometimes they are.