Correct option (d) glycoproteins and glycolipids
Explanation:
In the cell membrane, oligosaccharides do not occur freely but are attached to the extemal surface of phospholipids and proteins forming glycolipids and glycoproteins respectively. They form cell coat (glycocalyx) which acts as recognition centre, site for attachment and provides antigen specificity to cell membranes, blood grouping and matching of tissues in transplantation of organs.