[A] : The plasmalemmas of animals cells typically have the oligosaccharide chains of their glycolipids and exposed freely on their surfaces .
[R] : These play important roles in immunological responses , in cell-cell adhesion and identification of cell surface changes.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false