The correct option is B Plasmmalemma
The plasmalemma or plasma membrane of a cell keep the contents separate from the surrounding environment. It is composed of lipids and proteins. Some of the proteins are fixed and some can move about within the cell membrane. A number of proteins are involved in transporting molecules into and out of the cell, while others help maintain cell structure, act as receptors or take part in chemical reactions as enzymes. RNA is absent in plasmalemma. The telomerase is the important part of the chromosome. The telomerase contains RNA and it protects the chromosome from being cut. The nucleolus also contains proteins and RNAs that are not related to ribosome assembly and a number of new functions for the nucleolus have been identified. Ribosomes contain RNA and proteins.